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Four species of the callichirid ghost shrimp genus Corallianassa Manning, 1987 are recognised in Hawaii based on evidence from morphology and the CO1 gene. Corallianassa borradailei (De Man, 1928) is a widespread Indo-West Pacific species now confirmed for Hawaii. Corallianassa lanceolata Edmondson, 1944 is an endemic species similar to C. assimilis (De Man, 1928) from Indonesia and Guam. Corallianassa martensi (Miers, 1884) is also a widespread Indo-West Pacific species. Callianassa (Callichirus) winslowi Edmondson, 1944 (Hawaii), Callianassa (Callichirus) nakasonei Sakai, 1967 (Japan) and Callianassa haswelli Poore & Griffin, 1979 (Australia) are treated as junior subjective synonyms of C. martensi. Callianassa (Callichirus) oahuensis Edmondson, 1944, long treated as a junior synonym of C. borradailei, is revived as a valid species of Corallianassa. The four species differ in the shape and dorsal setae of the telson, the extent of the carina along the upper margin of the major cheliped palm, the attitude of the rostrum, and the shape of the maxilliped 3.

Corallianassa oahuensis (Edmondson, 1944) comb. nov. (Figs 6, 7, 8e–h, 9d–f) Callianassa (Callichirus) oahuensis Edmondson, 1944: 56–59, fig. 10. Callianassa oahuensis.— Edmondson 1946: 262, fig. 159g, h. Material examined. USA, Hawaii, Oahu, Hanauma Bay, C.H. Edmondson, 29 November 1938, BPBM S4594 (holotype female, 12 mm); C.H. Edmondson, no date, BPBM S4596 (1 specimen); Oahu, Waikiki, J.M. Ostergaard, 16 Jun 1961, BPBM S6140 (6 specimens). Oahu, Kaneohe Bay, patch reef N of Ahu’olaka Island, 0–2 m, 21.489°N, 157.825°W, G. Paulay, 27 May 2017, UF 45530 (ovigerous female, 9.7 mm). Diagnosis. Rostrum upturned; carapace anterolateral spines with mesial buttress. Maxilliped 3 ischium-merus 2.4 times as long as wide; merus tapering; propodus, free distal margin transverse. Major cheliped ischium lower margin with 8–10 oblique spines increasing in length distally; merus lower margin with 4–8 small oblique spines; palm as long as wide, upper margin carinate along more than proximal half and along distal quarter. Minor cheliped merus lower margin with 2 or 3 oblique spines; palm 1.3 times as long as wide, rectangular; fingers as long as palm, curved. Uropodal endopod 2 times as long as wide; anterior margin slightly convex; posterior margin convex; apex broadly rounded, flat. Uropodal exopod posterior margin slightly concave; proximal article with sharp spine overlapping endopod and smaller accessory proximal lobe. Telson tapering to about two-thirds basal width from basal lobes, 1.7 times as wide as long; posterior margin with medial lobe more prominent than posterolateral corners; dorsal surface with about 6 pairs of fine setae in row on transverse ridge. Size. Cl. to 12 mm. Colour. Carapace with paired orange anterodorsal patches; remainder of carapace, pleon white. Antennular peduncle article 3 orange; flagella orange-red. Antennal peduncle articles with orange patches; flagellum orangered. Maxilliped 3 with patches of orange. Cheliped meri, carpi with orange patches concentrated on upper margin; propodi mostly orange, with white patch at midpoint; fingers orange. Pereopods 2, 3 with orange patches on upper margins of carpus, propodus. Pereopods 4, 5 white (Fig. 7a, b). Distribution. USA, Hawaii, Oahu (type locality: Hanauma Bay) Remarks. The holotype of Callianassa (Callichirus) oahuensis Edmondson, 1944 (BPBM S4594) was examined by KL and compared with Edmondson’s (1944) figures and those of UF 45530. The holotype plus the material listed above differ from C. borradailei in the discontinuous low carina along the upper margin of the major cheliped palm (flange-like in C. borradailei), the relatively shorter and more tapered telson (1.7 vs 1.5 times wide as long), the absence of middorsal spiniform setae on the telson (3 or 4 pairs present), the upturned rostrum (horizontal) and the narrower maxilliped 3 (ischium-merus 2.4 vs 1.8 times as long as wide) with a more tapered merus. Callianassa (Callichirus) oahuensis Edmondson, 1944 has only ever been treated as a synonym of Corallianassa borradailei (Manning 1987, Komai et al. 2015). Here, we recognise it as an accepted species of Corallianassa.

Corallianassa lanceolata (Edmondson, 1944) Callianassa (Callichirus) lanceolata Edmondson, 1944: 52–53, fig. 8. Callianassa lanceolata.— Edmondson 1946: 262, fig. 159f. Glypturus lanceolatus. — Sakai 1999: 83.— Sakai 2005: 142.— Sakai 2011: 435. Corallianassa lanceolata.— Komai et al. 2015: 15, 18, 51–54. Material examined. USA, Hawaii, Northwestern Hawaiian Islands, Pearl and Hermes Reef, T. T. Dranga, April 1927, BPBM S2735 (2 specimens). Diagnosis. Rostrum upturned; carapace anterolateral spines triangular, short. Maxilliped 3 ischium-merus 2.5 times as long as wide; merus mesiodistal margin convex; propodus, free distal margin transverse. Major cheliped ischium lower margin with 2 small distal spines; merus lower margin with row of diminishing denticles; palm as long as wide. Minor cheliped merus lower margin smooth; palm 1.3 times as long as wide, rectangular; fingers as long as palm, curved. Uropodal endopod 3 times as long as wide; anterior margin sinuous; posterior margin convex; apex attenuated. Uropodal exopod posterior margin strongly concave in adult. Telson slightly tapering, 1.7 times as wide as long; posterior margin with medial lobe more prominent than posterolateral corners; dorsal surface with about 6 pairs of fine setae separated by median gap on transverse ridge. Size. Cl. to 9 mm. Distribution. USA, Hawaii: Oahu, Pearl and Hermes Reef (type locality: Hanauma Bay) Remarks. Corallianassa lanceolata resembles C. assimilis (De Man, 1928) from Indonesia and Guam but has a more attenuated uropodal endopod. Komai et al. (2015) noted that Callianassa (Callichirus) nakasonei Sakai, 1967, synonymised with this species by Sakai’s (2011), is instead a synonym of Corallianassa martensi., Published as part of Poore, Gary C. B., Longenecker, Ken & Tudge, Christopher C., 2023, Reappraisal of Hawaiian species of Corallianassa Manning, 1987 (Crustacea: Axiidea: Callichiridae), pp. 277-289 in Zootaxa 5249 (2) on page 281, DOI: 10.11646/zootaxa.5249.2.5, http://zenodo.org/record/7687362, {"references":["Edmondson, C. H. (1944) Callianassidae of the Central Pacific. Bernice P. Bishop Museum Occasional Paper, 18, 35 - 61.","Edmondson, C. H. (1946) Reef and shore fauna of Hawaii. Bernice P. Bishop Museum Special Publication, 22, 1 - 381.","Sakai, K. (1999) Synopsis of the family Callianassidae, with keys to subfamilies, genera and species, and the description of new taxa (Crustacea: Decapoda: Thalassinidea). Zoologische Verhandelingen, 326, 1 - 152. [https: // repository. naturalis. nl / pub / 219414]","Sakai, K. (2005) Callianassoidea of the world (Decapoda: Thalassinidea). Crustaceana Monographs, 4, 1 - 285. https: // doi. org / 10.1163 / 9789047416890","Sakai, K. (2011) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Komai, T., Maenosono, T. & Osawa, M. (2015) Records of three species of callianassid ghost shrimp from the genera Glypturus Stimpson, 1866 and Corallianassa Manning, 1987 (Crustacea: Decapoda: Axiidea) from the Ryukyu Islands, Japan, with remarks on the taxonomic status of the two genera. Fauna Ryukyuana, 27, 13 - 59.","De Man, J. G. (1928) A contribution to the knowledge of twenty-two species and three varieties of the genus Callianassa Leach. Capita Zoologica, 2, 1 - 56.","Sakai, K. (1967) Three new species of Thalassinidea (Decapoda, Crustacea) from Japan. Researches on Crustacea, 3, 39 - 51. https: // doi. org / 10.18353 / rcustacea. 3.0 _ 39"]}

Corallianassa martensi (Miers, 1884) (Figs 3–5, 9g, h) Callianassa sp. — Haswell 1882: 167–168. Callianassa martensi Miers, 1884: 13–15, pl. 1 fig. 1.— Sakai 1984: 99–101 (part), fig. 2 (figure of holotype).— Dworschak 1992: 200, fig. 8a–e. Callianassa (Callichirus) winslowi Edmondson, 1944: 59–61, fig. 11 (type locality, Hawaii) syn. nov. Callianassa winslowi.— Edmondson, 1946: 262, fig. 159i. Callianassa (Callichirus) nakasonei Sakai, 1967: 46–47, fig. 3 (type locality, Tonaki I., Ryuku Is, Japan). Callianassa haswelli Poore & Griffin, 1979: 263–266, figs 26, 27 (type locality: Australia, Qld, Whitsunday Group). Callianassa martensi.— Sakai 1984: 99–101. Callianassa nakasonei.—Sakai 1987: 306 (list). Glypturus haswelli.— Sakai 1999: 82.—Davie 2002: 460.— Sakai 2005: 142.— Sakai 2011: 434–435. Glypturus martensi.— Sakai 2011: 437–437. Glypturus nakasonei.— Sakai 2011: 430 (as junior synonym of G. lanceolatus) Neocallichirus winslowi.— Sakai 2011: 465. Corallianassa martensi.— Dworschak 2014: 233, figs 2, 10c. — Komai et al. 2015: 40–51, figs 14–19, 20D–F. — Poore et al. 2019: 144.— Robles et al., 2020. Corallianassa winslowi.— Komai et al. 2015: 15 ff. Corallianassa haswelli.— Komai et al. 2015: 15, 50. — Poore et al. 2019: 144.— Robles et al. 2020. Material examined. USA, Hawaii, Maui I., C. Winslow, 4 April 1860, USNM 63255 (holotype male, 17 mm; paratype female of Callianassa (Callichirus) winslowi Edmondson, 1944); Honolulu, Kaneohe Bay, S end Ahu’olaka I., 21.4588°N, 157.8019°W, FMNH invert team, 22 May 2017, 0–2 m, patch reef, UF 45445 (female, 9.7 mm). Tonga, Wataloa, Vava’u, intertidal sandflat, NMV J62121 (male, 15 mm). Papua New Guinea, Kavieng area, intertidal sandflat, MNHN-IU-2014-2070 (1 juvenile, 3.0 mm). French Polynesia, Moorea, NW Motus, sand flats, 17.489335°S, 149.913178°W, UF 23948 (female, 11.4 mm). Moorea (near Nihimaru river estuary), nearshore sand flat, 17.535°S, 149.906°W, UF 16469 (juvenile, 3.6 mm). Tuamotu, Makemo Atoll, intertidal reef flat, UF 18569 (1 ovigerous female, 11.3 mm). Australia. Northern Territory, New Year Island, intertidal coral platform, 10.9°S, 133.033°E, NMVJ11176 (male, 8.1 mm). Qld, Masthead I., Capricorn Group, NMV J9290 (female paratype of Callianassa haswelli Poore & Griffin, 1979, without chelipeds, 8.3 mm). Diagnosis. Rostrum horizontal; carapace anterolateral spines triangular. Maxilliped 3 ischium-merus 2–2.4 times as long as wide; merus tapering; propodus free distal margin oblique, or transverse. Major cheliped ischium lower margin with obsolete teeth (juvenile), or with 2–8 oblique spines increasing in length distally; merus lower margin with 1–3 proximal spines or denticulate blade; palm as long as wide (rarely slightly longer than wide), sometimes with obsolete teeth along lower margin, upper margin obscurely carinate along proximal half. Minor cheliped merus lower margin with 1 proximal spine, or smooth; palm 1.3–1.5 times as long as wide, rectangular; fingers as long as palm, curved. Uropodal endopod 2.0–2.5 times as long as wide; anterior margin convex with inflexion about twothirds along; posterior margin almost straight, or convex; apex rounded, flat. Uropodal exopod posterior margin strongly concave in adult, less so in juveniles; proximal article with blunt lobe overlapping endopod, sometimes with accessory spine. Telson tapering to about three-quarters basal width from basal lobes, 1.5–1.7 times as wide as long; posterior margin with medial lobe more prominent than posterolateral corners; dorsal surface with about 6 pairs of fine setae separated by median gap on transverse ridge. Size. Cl. to 17 mm. Colour. Carapace with two yellow-orange bands, one anterior, second across middle of dorsal oval; remainder of carapace, pleon white.Antennular peduncle article 2 with distal red band; flagella white.Antennal peduncle article 4 with distal red band; flagellum with red transverse bands every 2 or 3 segments. Maxilliped 3 unknown. Cheliped meri, carpi with pale yellow-orange patches concentrated on upper margin; propodi palms with 2 transverse pale yellow-orange bands; dactylus yellow-orange. Pereopods 2–5 white (Fig. 7c). Distribution. Western and Central Indo-Pacific (Mauritius [type locality], throughout Indian Ocean to Ryuku Islands, Japan; new localities: Hawaii, Tonga, Papua New Guinea, N and NE Australia); intertidal to 6 m. Remarks. Corallianassa martensi was redescribed in detail by Dworschak (2014) and again by Komai et al. (2015) who provided an extensive synonymy. The species is recognised by the concave posterior margin of the uropodal exopod, most evident in large individuals. The carina on the upper margin of the palm of the major cheliped extends only halfway along. The merus of maxilliped 3 tapers distally. The telson is much wider than long; the setae on its dorsal face cluster in two groups with a medial gap between. The rostrum, carapace anterolateral spines, telson and uropods of Callianassa (Callichirus) winslowi Edmondson, 1944 place the species in Corallianassa. The types from Hawaii (USNM 63255) were examined by CCT and compared with Edmondson’s (1944) figures and with those of specimen UF 45445, also from Hawaii. The carina running halfway along the upper margin of the major cheliped, noted by Dworschak (2014) and Komai et al. (2015) in C. martensi, was confirmed; the major cheliped ischium has two distal teeth and the merus two proximal teeth (Fig. 4o), again consistent with earlier descriptions of this species. The telson (damaged in the types) has a medial lobe on the posterior margin and the transverse dorsal ridge has a gap between groups of submedial setae. These features are consistent with those of Corallianassa martensi, with which it is here synonymised. Hawaii can be added to the species’ distribution. UF 45445 is one of two specimens from Kaneohe Bay here illustrated – the other is C. oahuensis redescribed below. The shapes of the telson, carina on the major cheliped palm, spine on the uropodal proximal article of the endopod and the angle of the rostrum differ (cf. Figs 4h–n, 5). C. (C.) winslowi was placed in Neocallichirus by Sakai (2011) without comment. Callianassa haswelli has been synonymised with C. martensi (Sakai 1984, 1988), suggested as a synonym of C. nakasonei Sakai, 1967 (Manning 1987) but in other literature has been treated as a valid species. Relying on Poore & Griffin’s figures, Komai et al. (2015) observed that C. haswelli differs from C. martensi in the relatively shorter antennular peduncle article 3 and the different shapes of the propodus of maxilliped 3 but these differences are subtle. The posterior margin of the uropodal exopod is more concave in some individuals than others but this seems not size-related (cf. Figs 3a, h, o, 4a, h, 5a, h; Dworschak 2014: Fig. 2i, p). The specimen from Tonga differs from previous descriptions in having obscure serrations along the lower margin of the major cheliped merus and the uropodal endopod being not as tapered from the base (Fig. 3a, e) as in published figures (Sakai 1984: fig. 2; Dworschak 2014: fig. 2; Komai et al. 2015: figs 16, 18). The CO1 mitochondrial gene of a juvenile of cl. 3.4 mm from Moorea (UF 16469) is 100% (BS) similar to that of UF 45445 from Hawaii (Fig. 1), both specimens identified as C. martensi. The telson of the juvenile is consistent with larger specimens but the uropodal exopod is not as expanded distally and rostrum is not spine-like. Robles et al. (2020) found some genetic difference between one individual from Papua New Guinea (MNHN-IU-2014-2070) and two others, one from Tonga (to the east) and the other from Cocos (Keeling) Islands (to the west). The tapering telson and short carina on the cheliped palm are seen in all specimens at hand. In most specimens the merus of the major cheliped has two proximal teeth on the lower margin but one from Tuamotu (unsequenced) has stronger dentition (Fig. 5e)., Published as part of Poore, Gary C. B., Longenecker, Ken & Tudge, Christopher C., 2023, Reappraisal of Hawaiian species of Corallianassa Manning, 1987 (Crustacea: Axiidea: Callichiridae), pp. 277-289 in Zootaxa 5249 (2) on pages 281-285, DOI: 10.11646/zootaxa.5249.2.5, http://zenodo.org/record/7687362, {"references":["Miers, E. J. (1884) On some crustaceans from Mauritius. Proceedings of the Zoological Society of London, 1884, 10 - 17, pl. 1. https: // doi. org / 10.1111 / j. 1096 - 3642.1884. tb 02802. x","Haswell, W. A. (1882) Catalogue of the Australian stalk-and sessile-eyed Crustacea. Australian Museum, Sydney, xxiv + 324 pp. https: // doi. org / 10.5962 / bhl. title. 1948","Sakai, K. (1984) Some thalassinideans (Decapoda: Crustacea) from Heron Is., Queensland, eastern Australia, and a new species of Gourretia from East Africa. The Beagle, Occasional Papers of the Northern Territory Museum of Arts and Sciences, 1, 95 - 108. https: // doi. org / 10.5962 / p. 320153","Dworschak, P. C. (1992) The Thalassinidea in the Museum of Natural History, Vienna; with some remarks on the biology of the species. Annalen des Naturhistorischen Museums in Wien, Series B, 93, 189 - 238.","Edmondson, C. H. (1944) Callianassidae of the Central Pacific. Bernice P. Bishop Museum Occasional Paper, 18, 35 - 61.","Edmondson, C. H. (1946) Reef and shore fauna of Hawaii. Bernice P. Bishop Museum Special Publication, 22, 1 - 381.","Sakai, K. (1967) Three new species of Thalassinidea (Decapoda, Crustacea) from Japan. Researches on Crustacea, 3, 39 - 51. https: // doi. org / 10.18353 / rcustacea. 3.0 _ 39","Poore, G. C. B. & Griffin, D. J. G. (1979) The Thalassinidea (Crustacea: Decapoda) of Australia. Records of the Australian Museum, 32, 217 - 321. https: // doi. org / 10.3853 / j. 0067 - 1975.32.1979.457","Sakai, K. (1999) Synopsis of the family Callianassidae, with keys to subfamilies, genera and species, and the description of new taxa (Crustacea: Decapoda: Thalassinidea). Zoologische Verhandelingen, 326, 1 - 152. [https: // repository. naturalis. nl / pub / 219414]","Sakai, K. (2005) Callianassoidea of the world (Decapoda: Thalassinidea). Crustaceana Monographs, 4, 1 - 285. https: // doi. org / 10.1163 / 9789047416890","Sakai, K. (2011) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Dworschak, P. C. (2014) The Axiidea (Crustacea, Decapoda) of Cocos (Keeling) and Christmas Islands, with description of a new species of Eucalliax Manning & Felder, 1991. Raffles Bulletin of Zoology Supplement, 30, 230 - 245.","Komai, T., Maenosono, T. & Osawa, M. (2015) Records of three species of callianassid ghost shrimp from the genera Glypturus Stimpson, 1866 and Corallianassa Manning, 1987 (Crustacea: Decapoda: Axiidea) from the Ryukyu Islands, Japan, with remarks on the taxonomic status of the two genera. Fauna Ryukyuana, 27, 13 - 59.","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","Robles, R., Dworschak, P. C., Felder, D. L., Poore, G. C. B. & Mantelatto, F. L. (2020) A molecular phylogeny of Callianassidae and related families (Crustacea: Decapoda: Axiidea) with morphological support. Invertebrate Systematics, 34, 113 - 132. https: // doi. org / 10.1071 / IS 19021","Sakai, K. (1988) A new genus and five new species of Callianassidae (Crustacea: Decapoda: Thalassinidea) from northern Australia. The Beagle, Occasional Papers of the Northern Territory Museum of Arts and Sciences, 5, 51 - 69. https: // doi. org / 10.5962 / p. 260916","Manning, R. B. (1987) Notes on western Atlantic Callianassidae (Crustacea: Decapoda: Thalassinidea). Proceedings of the Biological Society of Washington, 100, 386 - 401. [https: // biodiversitylibrary. org / page / 34570790]"]}

Corallianassa borradailei (De Man, 1928) (Figs 3, 8a–d, 9a–c) Callianassa (Callichirus) longiventris var. borradailei De Man, 1928 a: 27. Corallianassa borradailei.— Manning 1987: 394–395, figs 7–9.— Komai et al. 2015: 29–39, figs 8–13, 20A–C (redescription, full synonymy, discussion). Material examined. USA, Hawaii, Oahu, Waikiki, C.H. Edmondson, February 1931, BPBM S4595 (1 specimen); Hawaii [as Sandwich Islands], NHMUK 1859:79 (3 females identified by Paul. F. Clark). Mariana Islands, Guam, S and W coasts, seagrass beds, 13.5°N, 144.8°E, 0–1 m, UF 27328, UF 27340, UF 27343, UF 27351 (2 males, 2 females). Tonga, sandflat, intertidal, G.C.B. Poore, 12 Oct 2011, NMV J62119 (2 females, 13.7 mm). French Polynesia, Moorea, sandflats and mangroves, 0–1.5 m: Papetoai, UF 15485 (ovigerous female), UF 23992 (female); Pihaena, UF 23543 (juvenile), UF 24022 (male); Haapiti, UF 16253 (ovigerous female, with Bopyridae), UF 28963 (2 females), UF 28964 (ovigerous female), MNHN IU-2014-10468 (2 females, 10.9, 11.1 mm), IU-2014-10469 (4 females, 8.4–10.8 mm), IU-2014-10473 (2 females, 6.5, 11.0 mm). Diagnosis. Rostrum horizontal, sometimes slightly upturned; carapace anterolateral spines evenly tapered, slightly curved inwards. Maxilliped 3 ischium-merus 1.8 times as long as wide; merus mesiodistal margin convex; propodus free distal margin transverse. Major cheliped ischium lower margin with 6–8 oblique spines increasing in length distally; merus lower margin with 5–9 oblique spines diminishing distally; palm as long as wide, upper margin carinate, blade-like along whole length. Minor cheliped merus lower margin with 2 or 3 oblique spines; minor cheliped palm as long as wide; palm rectangular; fingers as long as palm, curved. Uropodal endopod 1.5 times as long as wide; anterior margin evenly convex; posterior margin convex; apex broadly rounded, flat. Uropodal exopod posterior margin almost straight; proximal article with sharp spine overlapping endopod and smaller accessory proximal lobe. Telson tapering to about half basal width from midpoint, 1.5 times as wide as long; posterior margin evenly slightly convex; dorsal surface with 3 or 4 pairs of spiniform setae lateral to longer fine setae on transverse ridge. Size. Cl. to 15 mm. Distribution. Western, Central and Eastern Indo-Pacific (Maldives [type locality]; Chagos Archipelago; Indonesia; Tonga; Marianas; Japan, Ryukyus; Fiji; French Polynesia; Hawaii); intertidal, subtidal (Komai et al. 2015). Remarks. Corallianassa borradailei was redescribed in detail by Komai et al. (2015) after previously being widely confused with C. coutierei. The species is characterised by the continuous, flange-like carina along the upper margins of the carpus and palm of the major cheliped, the telson tapering only from the midpoint, with pairs of middorsal spiniform setae in addition to fine setae, and the convex mesiodistal margin of the maxilliped 3 merus. Three females from Hawaii (NHMUK 1859:79) were identified by Manning (1987) who noted the dorsal carina on the palm extending distally into a distinct flange, a feature characterising this species. The same specimens were seen by Ngoc-Ho (2002) and confirmed for this character by Paul Clark (NHMUK; 22 July 2022). Only one further specimen was found in the BPBM collections., Published as part of Poore, Gary C. B., Longenecker, Ken & Tudge, Christopher C., 2023, Reappraisal of Hawaiian species of Corallianassa Manning, 1987 (Crustacea: Axiidea: Callichiridae), pp. 277-289 in Zootaxa 5249 (2) on pages 279-281, DOI: 10.11646/zootaxa.5249.2.5, http://zenodo.org/record/7687362, {"references":["De Man, J. G. (1928) A contribution to the knowledge of twenty-two species and three varieties of the genus Callianassa Leach. Capita Zoologica, 2, 1 - 56.","Manning, R. B. (1987) Notes on western Atlantic Callianassidae (Crustacea: Decapoda: Thalassinidea). Proceedings of the Biological Society of Washington, 100, 386 - 401. [https: // biodiversitylibrary. org / page / 34570790]","Komai, T., Maenosono, T. & Osawa, M. (2015) Records of three species of callianassid ghost shrimp from the genera Glypturus Stimpson, 1866 and Corallianassa Manning, 1987 (Crustacea: Decapoda: Axiidea) from the Ryukyu Islands, Japan, with remarks on the taxonomic status of the two genera. Fauna Ryukyuana, 27, 13 - 59.","Ngoc-Ho, N. (2002) A new species of Calliapagurops de Saint Laurent from the Philippines with a discussion of the taxonomic position of the genus (Thalassinidea, Callianassidae). Crustaceana, 75, 539 - 549. https: // doi. org / 10.1163 / 156854002760095589"]}

Corallianassa oahuensis (Edmondson, 1944) comb. nov. (Figs 6, 7, 8e–h, 9d–f) Callianassa (Callichirus) oahuensis Edmondson, 1944: 56–59, fig. 10. Callianassa oahuensis.— Edmondson 1946: 262, fig. 159g, h. Material examined. USA, Hawaii, Oahu, Hanauma Bay, C.H. Edmondson, 29 November 1938, BPBM S4594 (holotype female, 12 mm); C.H. Edmondson, no date, BPBM S4596 (1 specimen); Oahu, Waikiki, J.M. Ostergaard, 16 Jun 1961, BPBM S6140 (6 specimens). Oahu, Kaneohe Bay, patch reef N of Ahu’olaka Island, 0–2 m, 21.489°N, 157.825°W, G. Paulay, 27 May 2017, UF 45530 (ovigerous female, 9.7 mm). Diagnosis. Rostrum upturned; carapace anterolateral spines with mesial buttress. Maxilliped 3 ischium-merus 2.4 times as long as wide; merus tapering; propodus, free distal margin transverse. Major cheliped ischium lower margin with 8–10 oblique spines increasing in length distally; merus lower margin with 4–8 small oblique spines; palm as long as wide, upper margin carinate along more than proximal half and along distal quarter. Minor cheliped merus lower margin with 2 or 3 oblique spines; palm 1.3 times as long as wide, rectangular; fingers as long as palm, curved. Uropodal endopod 2 times as long as wide; anterior margin slightly convex; posterior margin convex; apex broadly rounded, flat. Uropodal exopod posterior margin slightly concave; proximal article with sharp spine overlapping endopod and smaller accessory proximal lobe. Telson tapering to about two-thirds basal width from basal lobes, 1.7 times as wide as long; posterior margin with medial lobe more prominent than posterolateral corners; dorsal surface with about 6 pairs of fine setae in row on transverse ridge. Size. Cl. to 12 mm. Colour. Carapace with paired orange anterodorsal patches; remainder of carapace, pleon white. Antennular peduncle article 3 orange; flagella orange-red. Antennal peduncle articles with orange patches; flagellum orangered. Maxilliped 3 with patches of orange. Cheliped meri, carpi with orange patches concentrated on upper margin; propodi mostly orange, with white patch at midpoint; fingers orange. Pereopods 2, 3 with orange patches on upper margins of carpus, propodus. Pereopods 4, 5 white (Fig. 7a, b). Distribution. USA, Hawaii, Oahu (type locality: Hanauma Bay) Remarks. The holotype of Callianassa (Callichirus) oahuensis Edmondson, 1944 (BPBM S4594) was examined by KL and compared with Edmondson’s (1944) figures and those of UF 45530. The holotype plus the material listed above differ from C. borradailei in the discontinuous low carina along the upper margin of the major cheliped palm (flange-like in C. borradailei), the relatively shorter and more tapered telson (1.7 vs 1.5 times wide as long), the absence of middorsal spiniform setae on the telson (3 or 4 pairs present), the upturned rostrum (horizontal) and the narrower maxilliped 3 (ischium-merus 2.4 vs 1.8 times as long as wide) with a more tapered merus. Callianassa (Callichirus) oahuensis Edmondson, 1944 has only ever been treated as a synonym of Corallianassa borradailei (Manning 1987, Komai et al. 2015). Here, we recognise it as an accepted species of Corallianassa., Published as part of Poore, Gary C. B., Longenecker, Ken & Tudge, Christopher C., 2023, Reappraisal of Hawaiian species of Corallianassa Manning, 1987 (Crustacea: Axiidea: Callichiridae), pp. 277-289 in Zootaxa 5249 (2) on pages 285-287, DOI: 10.11646/zootaxa.5249.2.5, http://zenodo.org/record/7687362, {"references":["Edmondson, C. H. (1944) Callianassidae of the Central Pacific. Bernice P. Bishop Museum Occasional Paper, 18, 35 - 61.","Edmondson, C. H. (1946) Reef and shore fauna of Hawaii. Bernice P. Bishop Museum Special Publication, 22, 1 - 381.","Miers, E. J. (1884) On some crustaceans from Mauritius. Proceedings of the Zoological Society of London, 1884, 10 - 17, pl. 1. https: // doi. org / 10.1111 / j. 1096 - 3642.1884. tb 02802. x","De Man, J. G. (1928) A contribution to the knowledge of twenty-two species and three varieties of the genus Callianassa Leach. Capita Zoologica, 2, 1 - 56.","Manning, R. B. (1987) Notes on western Atlantic Callianassidae (Crustacea: Decapoda: Thalassinidea). Proceedings of the Biological Society of Washington, 100, 386 - 401. [https: // biodiversitylibrary. org / page / 34570790]","Komai, T., Maenosono, T. & Osawa, M. (2015) Records of three species of callianassid ghost shrimp from the genera Glypturus Stimpson, 1866 and Corallianassa Manning, 1987 (Crustacea: Decapoda: Axiidea) from the Ryukyu Islands, Japan, with remarks on the taxonomic status of the two genera. Fauna Ryukyuana, 27, 13 - 59."]}

Pleuroprion chuni (zur Strassen, 1902) (Figs 1 – 8) Antares chuni zur Strassen, 1902: 687 – 688, fig. 4. Pleuroprion chuni.—zur Strassen, 1903: 31.—Barnard, 1914: 216.— Kensley, 1975: 38 (in table).— Kensley, 1978: 33–34, fig. 15E. Material examined: Paralectotype (herein designated), female, 10 mm, German Deep-Sea Expedition 1898/99, station 104, cat. number ZMB 19154. Lectotype, male, same data as holotype. Other material: Non-ovigerous female, length not recorded, South Africa, Still Bay, 35ºS, 22ºE, 200 m (station SST-11-D-5), SAM A14025. Description of paralectotype (female) (Figs 1–4): Body (Fig. 1A; completely broken, head, pereonite 1 and pleotelson missing) width of pereonites subparallel (pereonites completely broken and squeezed, thus no widthlength relationship is given). Pereonites 2–7 with large lateral extensions, pereonite 4 with 2 dorsal spines. Pereonites 5–7 subparallel and of similar length and width. Pereonite 5–7 each with 2 dorsal spines. Pleonite 1 not fused to pleotelson, without middorsal spines, lateral extension present. Remaining pleotelson with 1 dorsal spine and lateral extensions on anterior part. Antennula (Fig. 1B) peduncle article 1 wide and short, narrowing towards distal end; distally with 2 penicillate setae; article 2 0.7 times width of article 1, with 2 penicillate setae and few slender setae; flagellum article 1 short, with 1 long, slender seta distally, article 2 2.6 times longer that article 1, 2.8 times longer than wide, with 8 aesthetascs, 1 penicillate seta and 4 slender setae distally. Antenna (Fig. 1C) flagellum distally with long unguis. Labrum (Fig. 1D) with fine setae. Right mandible (Fig. 2A) molar smooth, slightly dentate on anterior edge, with some longer setae. Lacinia mobilis like structure lobate. Spine row comprising 3 dentate spines. Incisor with 2 lobes and 3 smaller teeth. Left mandible (Fig. 2B) molar serrated, with 3 pappose setae, outside densley fringed with numerous fine small setae. Lacinia mobilis with two major lobes and one small indication of third lobe. Spine row comprising presumably 1 dentate spine; incisor 4-toothed. Pereopod 4 (Fig. 2C, carpus to dactylus missing) basis, ischium and merus with long slender setae distally on inferior margin. Pereopod 5 (Fig. 3A), stout, with sparse setae; inferior margin of basis with 5 broom like setae; carpus and merus similar in length, carpus distally with one broom like seta, propodus 1.3 times longer than carpus and distally with one broom like seta. Dactylus partly broken. Pereopod 6 (Fig. 3B) similar in shape to pereopod 5, stout, with sparse setae; basis with 5 broom like setae; carpus and merus similar in length, propodus 1.2 times longer than carpus and 1.6 times longer than dactylus. Dactylus with 1 unguis and three stout setae (one setule, two broken). Pereopod 7 (Fig. 3C) similar in shape to pereopod 6, stout, with sparse setae; basis with at least 4 broom like setae; carpus and merus similar in length, propodus 1.3 times longer than carpus. Dactylus broken off. Pleopod 1 (Fig. 4A) peduncle with 9 coupling hooks; mesial margin of endopod and lateral margin of exopod fringed with plumose setae. Pleopod 2 (Fig. 4B) mesial margin of endopod and lateral margin of exopod fringed with plumose setae. Pleopod 3 (Fig. 4C) with expanded exo- and endopods; rami apically rounded. Uropod (Fig. 4D, E) slightly truncated anteriorly, tapering posteriorly with 6 plumose setae. Exopod very short, with one short robust seta, endopod tiny, with one robust seta. Lectotype male (Figs 5–8): Body (Fig. 5A, B) maximum length 9.8 mm; length 5.6 times largest width (pereonite 3) (excluding spines), width of pereonites subparallel. Body flattened in dorsal view with asellote appearance, with dorsal spines and lateral extensions. Pattern of spination as in female. Head fused to pereonite 1, suture absent; anterolateral spines in front of eyes; anterodorsal pair of spines. Eyes prominent, bulbous. Pereonite 1 lateral margin deep, convex, with one spine; middorsal pair of spines. Pereonites 2–4 of similar length, with lateral extensions and 2 dorsal spines each. Pereonite 2 0.8 times length of pereonite 4, pereonite 3 0.9 times length of pereonite 4. Pereonite 4 0.1 times body length; anterior and posterior parts constricted, ventral margin not notched (Fig. 5C). Pereonites 5–7 with lateral extensions and 2 dorsal spines each. Pereonite 5 0.7 times length of pereonite 4, pereonite 6 0.6 times length of pereonite 4, pereonite 7 0.5 times length of pereonite 4. Pleonite 1 not fused to pleotelson, without middorsal spines, lateral extensions present. Pleotelson with two dorsal spines and lateral extensions on anterior part; posterior end of pleotelson pointed and slightly dorsally orientated. Antennula (Fig. 6A) peduncle article 1 wide and short, narrowing towards distal end; distally with 2 penicillate setae; article 2 0.8 times width of article 1, medially with 3 penicillate setae and few slender setae; flagellum article 1 short, with 1 long, slender seta mediodistally, article 2 4.1 times longer that article 1, 4.9 times longer than wide, with 17 aesthetascs distally on lateral margin; few slender setae in between. Antenna (Fig. 6B) peduncle with 5 articles, articles 3 to 5 of similar lengths, inferior margin of penducle fringed with many long slightly plumose setae of same type; flagellum 0.6 times penduncle article 5, flagellum with 2 articles; article 1 distally with 1 long seta, article 2 0.9 length times article 1 length, distally with few slender setae. Claw broken. Left mandible (Fig. 6C) molar serrated with 2 pappose setae. Outside of molar fringed with numerous fine small setae; spine row with 3 strong dentate spines; lacinia mobilis reduced, one-lobed; incisor process with 6 lobes. Maxillula (Fig. 6D) lateral lobe with 9 cuspidate apical setae. Mesial lobe apically with 3 pappose setae. Maxilla (Fig. 6E) mesial lobe oblique margin with 9 robust papposerrate setae; middle lobe with 2 long papposerrate setae; lateral lobe with 2 long papposerrate setae. Maxilliped (Fig. 6F) endite ventrally with 1 slender setulate seta; distally with several pappose setae and some small simple setae; no coupling hooks visible. Palp article 1 short; article 2 with few long setae mesiodistally; article 3 longest palp article, with long, slender setae mesially; articles 4 and 5 distally with several long papposerrate setae. Epipodite distally pointed. Pereopod 1 (Fig. 7A) held close to mouthparts; basis distally with few slender setae; ischium short, several long slender setulate setae on inferior margin and distally on ischium; merus short, 0.7 times longer than wide, 4 long slender setulate setae on inferior margin; carpus 0.8 times longer than wide, inferior margin distally pointed, length 1.2 times merus length, inferior margin with long slender setulate setae; propodus length 2.4 times carpus length, 2.5 times longer than wide, numerous slender setulate setae on inferior margin, slender setae distally on superior margin; dactylus with unguis; unguis slender, dactylus and unguis together about same length of propodus. Pereopod 2 (Fig. 7B) basis short, inferior margin distally with several pappose setae and some single simple setae; ischium short, inferior margin with several pappose setae and some single simple setae; merus short, 1.6 times longer than wide, groups of long, pappose setae and some single simple setae on inferior margin; carpus-propodus long and narrow; carpus 4.9 times longer than wide, length 2.5 times merus length, groups of long, pappose setae and some single simple setae on inferior margin; propodus 9.5 times longer than wide, length 1.3 times carpus length, fringed with long, pappose setae and some single simple setae on inferior margin; dactylus long, slender, length 0.6 times propodus length, unguis present. Pereopods 3 and 4 (Fig. 7 C–D) similar to pereopod 2. Pereopods 5–7 (Fig. 7 E–G) similar in shape, stout, with sparse setae; basis of pereopods 5–6 with 6 penicillate setae on superior margin. Pereopod 7 basis with 8 penicillate setae. Carpus and propodus of pereopod 5 with two, respectively 1 penicillate setae, of pereopod 6 and 7 with one penicillate seta each; carpus and merus similar in length, propodus 1.3 to 1.4 times longer than carpus and 1.5 to 1.8 times longer than dactylus. Dactylus with single unguis. Uropod (Fig. 7H) slightly truncated anteriorly, tapering posteriorly with 12 plumose setae. Exopod very short, with one robust setae (broken), endopod tiny, with one robust setae (broken). Pleopod 1 (Fig. 8A) peduncle 2.9 times longer than wide, with 5 coupling hooks; exopod laterally with 13 plumose setae and distally with 9 apical plumose setae. Distolaterally with strong groove on its posterior face. Endopod shorter than exopod, laterally with 6 plumose setae and distally with at least 5 apical plumose setae. Pleopod 2 (Fig. 8B) peduncle with 3 coupling hooks; endopod with about 20 plumose setae apically and distally along mesial margin; exopod with around 31 plumose setae apically and along whole lateral margin; appendix masculina (Fig. 8C) fused as a single penial plate, styliform, straight, apically bifid, pointing sligthly mediodistally, 1.2 times longer than endopod. Pleopods 3–5 (Fig. 8 D–F) with expanded exo- and endopods; rami apically rounded, fine setae on margins. Pleopod 5 with 3 plumose setae on exopod. Remarks: The type material stored in the Museum für Naturkunde in Berlin, Germany, consists of three tubes, one with the remaining broken female paralectotype, the second one with some loose dissected parts, and the third one with the male lectotype being in a good shape. The poor condition of the female did not allow a full redescription. From the remaining part of the female and the male of Pleuroprion chuni no pronounced sexual dimorphism was visible. The lateral extensions of P. chuni are very characteristic for the species, reminding more of an asellote than of a valviferan, this being noted by zur Strassen (1902). Due to the poor condition of the female holotype, there is still uncertainty about the number and shape of the oostegites. Kensley (1978) stated that the coxae had acute spines. This is erroneous, as this can not be seen from the type material. He illustrated only the habitus (dorsal view, his fig. 15E) of one specimen, but the sex of the specimen was not mentioned (Kensley 1978). This same specimen was reillustrated by G.C.B. Poore in 1999 and provided additional detail. These illustrations revealed the important uropodal rami and the claw on the antennal flagellum, not clear on the types. Distribution: Off South Africa, Agulhas Bank, Still Bay at 156–200 m (zur Strassen 1902; Kensley 1975; Kensley 1978)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 4-14, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Kensley, B. (1975) Marine Isopoda from the continental shelf of South Africa. Annals of the South African Museum, 67 (4), 35 - 89.","Kensley, B. (1978) Guide to the marine isopods of Southern Africa. Trustees of the South African Museum, Cape Town, 173 pp."]}

Spectrarcturus toporoki (Kussakin, 1972) comb. nov. (Fig. 33) Pleuroprion toporoki Kussakin, 1972: 186–189, figs 5–6. — Kussakin, 1982: 432–435, figs 321–322. Material examined: Paratype female, ZIN RAS cat. no. 2/49344, Kobjakova R / V “Toporok”, station 46, 6 September 1948, South Kurile Islands, Ituruo Island. Diagnosis: Body with numerous large and small, robust, bluntly pointed spines; pereonite 4 0.18 times body length; evenly wide, sligthly longer than second and third together; pleotelson short, with several short spines, posterior margin rounded. All pleonites fused into pleotelson, only one pleonite visible. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna considerably shorter than body; short, robust. Spines on basis of pereopods 5 to 7. Oostegites present on pereopod 5, as small lobes. Male penis lanceolate, tapering evenly towards rounded distal end; appendix masculina long, distally curved, extending one-third of length beyond exopod. Distribution: Kurile Islands, at depths between 5 and 60 m (Kussakin 1972, 1982)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 45, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Kussakin, O. G. (1972) Isopoda from the coastal zone of the Kurile Islands. III. Three new arcturids from the Middle Kurils with taxonomic remarks on the family Arcturidae. Crustaceana, Supplement 3, 178 - 189.","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]"]}

Spectrarcturus hystrix (Sars, 1877) comb. nov. (Figs 29–30) Arcturus hystrix Sars, 1877: 250–251 (erroneously labelled 350–351).— Sars, 1885: 104–106, pl. IX, figs 23–26.— Norman, 1904: 446. Pleuroprion hystrix. — Hansen, 1916: 194–195, pl. XV, fig. 6a–b.— Gurjanova, 1936: 200, fig. 128.— Kussakin, 1982: 421–424, figs 313–314. Material examined: Syntypes, F1683, Norwegian North-Atlantic Expedition 1876–1878, stations 18, 124, 164, 4 females. Other material. Female, WH 233, stn. 1023; male, Voucher 52975, POS 456 IceAGE 2, stn. 873-6 EBS from DZMB 43.916. Diagnosis: Body with several long and slender, bluntly pointed spines; pair on anterior part of head; posteriorly row of spines across head; pereonite 1 with row of spines across pereonite; pereonites 2 and 3 with row of spines across pereonites; two rows of spines on pereonite 4; pereonite 4 0.2 times body length; trapezoid, 2.1 times longer than third pereonite. Pleotelson intermediate in length, with 5 pairs of long and slender spines near midline of pleotelson, lateral margins with spines; posterior part of pleotelson tapering towards bifid apex; pleotelson upturned distally. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna short, about 0.6 of total body length; slender, with 3 large spines on second segment; large spine laterodistally on third segment, spine laterodistally on fourth segment. Spines present on basis of pereopods 5–7. Oostegites present on pereopod 1–5. Male smaller than female. Pattern of spination as in females, spines smaller than in females and more robust; middle part of pereonite 4 narrow, without spines. Posterior part of pleotelson tapering towards bifid apex; cleft of apex not as pronounced an in females. Endo- and exopod fringed with fine setae, distally with plumose setae; endopod with 7 setae; exopod with 11 setae; endopod slightly longer than exopod; pleopod 2 appendix masculina long and curved in distal half, about 1/3 longer than expodite, fringed with fine setae. Remarks: The species differs from all other Spectrarcturus species in the pattern of spination of the body. Other characteristics are the shape of the pleotelson and the long distolateral spine on article 3 of the antenna. Distribution: Northernmost North Atlantic, Nordic Seas: the Faeroe Islands, Norway, Greenland, at depths between 600–1150 m (Hansen 1916).

Spectrarcturus murdochi (Benedict, 1898) comb. nov. (Figs 9–25) Arcturus murdochi Benedict, 1898: 49–50, fig. 9. Pleuroprion murdochi.— Richardson, 1899a: 855.— Richardson, 1900: 230.— Richardson, 1905: 342–344, figs 371–372.— Hansen, 1916: 195–196.— Boone, 1920: 30.— Gurjanova, 1936, 198–200, fig. 127.— Gurjanova, 1952: 176.— Schultz, 1969: 52, fig. 53a.— Kussakin & Mezhov, 1979: 149.— Kussakin, 1982: 424–427, figs 315–316. Spectrarcturus multispinatus Schultz, 1981: 67, fig. 2A–I. Syn. nov. Material examined: Pleuroprion murdochi, holotype, female, 10.5 mm (12 mm according to Richardson 1905) (USNM 7915), Point Barrow Expedition, 31 August 1883, Point Franklin, Alaska. Spectrarcturus multispinatus, holotype, female, 10 mm length (9 mm according to Schultz 1981) (USNM 181264) (holotype extensively fouled with bacteria), Hero 3-290, Little Nellefiske Bank, Greenland, 64°54´N, 53°38´W, 18 August 1968, 79– 85 m. New material: Illustrated or dissected specimens. Female, 7.6 mm (ZMH 43165), WH244 Stn 2002-3 (SW station revisited), 60°00.18´N, 46°31.02´W, 167 m, 1 November 2002, sediment as in stn 2001-3, 4.44°C, salinity 34.03, 749 individuals; male, 4.3 mm (ZMH 43166), WH244 Stn 2002-3, same data as before; female, 6.8 mm (ZMH 43167), WH244 Stn 2002-3, same data as before; preparatory female, 6.0 mm (ZMH 43168), WH 233 Stn 2001-3 (SW station), 59°59.99´N, 46°30.83´W, 161 m, 19 October 2001, sandy bottoms, with few small stones and rich in macroinvertebrates (corals, crinoids, ophiuroids, sponges), 5.88°C, salinity 34.53, 847 individuals; preparatory female, 5.9 mm (ZMH 43169), WH244 Stn 2002-3, same data as before; female, 7.6 mm (ZMH 43170), WH 233 Stn 2001-3, same data as before; female, 7.5 mm (ZMH 43171), WH 233 Stn 2001-3, same data as before; juvenile (manca 2), 2.1 mm (ZMH 43172) WH244 Stn 2002-3, same data as before; juvenile (manca 3), 3.3 mm (ZMH 43173), WH244 Stn 2002-3, same data as before; male, 4.1 mm (ZMH 43174), WH244 Stn 2002-3, same data as before; female, 7.2 mm (ZMH 43175), WH244 Stn 2002-3, same data as before. Further material (not catalogued material, deposited at ZMH, UI and ZMB): WH 233 Stn 1013, 63°36´N, 37°41´W, 237 m, 24 October 2001, sediment consisting mostly of sand, corals, sponges and mussel shells, 4.34°C, salinity 34.86, 13 individuals; WH 233 Stn 1016, 63°34´N, 39°18´W, 219 m, 25 October 2001, sediment as in stn 1013, 4.37°C, salinity 34.81, 4 individuals; WH 233 Stn 1023, 62°28´N, 40°39´W, 251 m, 26 October 2001, sediment as in stn 1013, 4.68°C, salinity 34.48, 1 individual; WH 233 Stn 1047, 60°18´N, 46°35´W, 154 m, 31 October 2001, sediment pure sand, 5.53°C, salinity 34.52, 7 individuals; WH 233 Stn 2001-4 (NW station), 63°07.44´N, 52°17.50´W, 162 m, 6 November 2001, sandy bottoms, with few small stones and rich in macroinvertebrates (corals, crinoids, ophiuroids, sponges), 5.74°C, salinity 34.83, 2 individuals; WH 268 Stn 2004-3 (SW station revisited), 59°59.94´N, 46°31.05´W, 23 October 2004, 160 m, sediment as in stn 2001-3, 6.22°C, salinity 34.67, 349 individuals; WH 268 Stn 2004-4 (NW station revisited), 63°07.22´N, 52°16.84´W, 152 m, 28 October 2004, sediment as in stn 2001-4, 4.48°C, salinity 33.96, 12 individuals. This material was referred to as Spectrarcturus multispinatus in Stransky & Brandt (2010) and Stransky & Svavarsson (2010). Diagnosis: Body with several large, bluntly pointed spines; 8 spines in transverse row on pereonite 1; pereonite 2 with 6 spines in transverse row, laterodistal margin anterior knob where spines are found on latter pereonites; pereonite 3 with 6 spines in transverse row and small anterolateral and posterolateral spines; pereonite 4 trapezoid, 1.8–2.5 times longer than third pereonite, with anterior transverse spine row with 6 spines, smaller anterolateral spine and small lateral spine or fork spine posterior to spine row; posterior spine row with 6 spines; pereonite 5 with 6 spines in transverse row, small anterolateral and posterolateral spines; pereonite 6 with 6 spines in transverse row, small anterolateral and posterolateral spines; pereonite 7 with 6 spines in transverse row, small posterolateral spine. Pleotelson long, with pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with smaller spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of female pleotelson bifid and slightly dorsally orientated. All pleonites fused into pleotelson, only one pleonite visible. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna intermediate in length, about 0.6 of total body length; robust. Spines present on basis of pereopods 5–7. Oostegites present at pereopods 1–5. Redescription of figured females (Figs 9–17): Body (Figs 9A, B, 10A, B, 11 A–C) length 5.9–10.5 mm; length 4.5 times largest width (excluding spines), increasing in width towards pereonite 4, decreasing in width from pereonite 4 to pereonite 7. Fine setae covering body. Head fused to pereonite 1, suture absent, small ventral notch on lateral margin; small lateral spine near anterior margin, 3 spines dorsally and dorsolaterally between eyes, posterior end of head with 6 spines, dorsal pair largest. Eyes prominent, bulbous. Pereonite 1 lateral margin deep, convex; 8 spines in transverse row on pereonite 1, dorsal pair largest. Pereonite 2 short, 0.3 times length of pereonite 4, 6 spines in transverse row, dorsal pair largest, laterodistal margin with anterior knob where spines are found on latter pereonites. Pereonite 3 0.4 times length of pereonite 4, with 6 spines in transverse row and small anterolateral and posterolateral spines. Pereonite 4 0.2 times body length; anterior transverse spine row with 6 spines, smaller anterolateral spine and small lateral spine or fork spine (see variation) posterior to spine row; posterior spine row with 6 spines (see variation), dorsal pair largest on body. Pereonite 5 0.4 times length of pereonite 4, with 6 spines in transverse row, small anterolateral and posterolateral spines. Pereonite 6 0.4 times length of pereonite 4, with 6 spines in transverse row, small anterolateral and posterolateral spines. Pereonite 7 0.4 times length of pereonite 4, with 6 spines in transverse row, small posterolateral spine. All pleonites fused into pleotelson, only one pleonite visible. Pleotelson with different pattern of spines from that of pereonites; pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with smaller spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of pleotelson bifid and slightly dorsally orientated. Oostegites on pereopods 1 – 5, largest on pereopod 5 (Figs 9B, 10A, 11A, 17 E–F). Antennula (Fig. 12A) short, reaching little beyond distal end of second peduncular segment of antenna; peduncle article 1 wide and short, distally with 1 penicillate and 1 slender seta, article 2 0.5 times width of article 1, distally with 4 penicillate setae; flagellum article 1 short, fine seta distally, article 2 2.3 times longer that article 1, 4.4 times longer than wide, with 4–5 aesthetascs (sometimes 3) and 2 penicillate setae (1 broken off in illustration) distally. Antenna (Fig. 12B) peduncle with 5 articles, articles 4 and 5 longest; flagellum 0.5 times penduncle article 5, flagellum with 3 articles and claw (partly broken off); flagellum with fine setae (mostly broken off); article 2 0.5 length times article 1 length; article 3 0.2 times article 1. Labrum (Fig. 12C) with fine setae. Right mandible (Fig. 12D) molar smooth, slightly dentate on anterior edge. Lacinia mobilis with 2 major lobes and 3–4 smaller lobes; spine row comprising 2 dentate spines. Incisor 3-toothed. Left mandible (Fig. 12E) molar smooth, lacinia mobilis 2-lobed; spine row comprising 3 dentate spines, incisor 3-toothed. Maxillula (Fig. 12F) mesial lobe with 3 long pappose setae distally and mesially one pappose and several fine, slender setae; lateral lobe with 10 cuspidate apical setae and 1 smaller robust apical seta. Maxilla (Fig. 12G) mesial lobe oblique margin with 9 robust papposerrate setae, 12 – 13 long, simple setae on anterior edge; middle lobe with 3 long pectinate, finely setulate setae; lateral lobe with 2 long pectinate, finely setulate setae. Maxilliped (Fig. 12H) endite ventrally with 4 slender setae; distally with 7 pappose setae; 3 or 4 large coupling hooks. Palp article 1 short; article 2 with several long simple setae mesiodistally and ventrally; article 3 longest palp article, with long, slender simple setae distally and on ventral surface; articles 4 and 5 distally with several long simple setae. Epipodite distally rounded. Pereopod 1 (Fig. 13A) held close to mouthparts; basis with several long simple setae distally; ischium short, several long setae on inferior margin and distally on ischium; merus short, 0.88 times longer than wide, several long simple setae and 1 small penicillate seta on inferior margin and distally, superior margin distally with 2 pectinate setae (broken); carpus 2.03 times longer than wide, length 1.7 times merus length, inferior margin with row of clavate distally setulate setae and long slender setae inbetween; propodus length 1.0 times carpus length, 2.1 times longer than wide, several clavate distally setulate setae and slender setae on inferior margin, pectinate and denticulate setae distally on superior margin; dactylus short, 0.2 times propodus length, distally with 3 long setae (2 broken), unguis absent. Pereopod 2 (Fig. 13B) basis short, superior margin distally forming spine, inferior margin with several slender simple setae; ischium short, inferior margin with several slender simple setae; merus-propodus long and narrow; merus long, 2.7 times longer than wide, groups of long, slender simple setae on inferior margin; carpus long, 4.3 times longer than wide, length 1.2 times merus length, groups of slender, long simple setae on inferior margin; propodus long, 9 times longer than wide, length 1.1 times carpus length, groups of slender, long simple setae on inferior margin; dactylus short, slender, length 0.1 times propodus length, unguis present. Pereopods 3 and 4 (Fig. 14A, B) similar to pereopod 2; conspicious spine on superior margin of basis; coxa with 2 spines. Pereopods 5–7 (Fig. 15 A–C) similar in shape, stout, with sparse setae; basis with prominent spine; carpus and merus similar in length, propodus 2.1 to 2.5 times longer than carpus and 1.7 to 2.2 times longer than dactylus. Dactylus with 2 ungui, secondary unguis robust. Pleopod 1 (Fig. 16A) peduncle 3.5 times longer than wide, with 3 coupling hooks; endopod distally with 5 apical plumose setae; expod as long as endopod, distally with 4 apical plumose setae. Pleopod 2 (Fig. 16B) with 2 coupling hooks; endopod with 7 apical plumose setae, exopod with 10 apical plumose setae. Pleopods 3–5 (Fig. 16 C–E) with expanded exo- and endopods; rami apically rounded; 2 plumose setae on endopod of pleopod 3; 1 plumose seta on endopod of pleopods 4 and 5. Uropod (Fig. 15D) rounded anteriorly, tapering posteriorly with 1 plumose seta; exopod 0.4 times endopod length, 2 apical setae with plumose shaft and short setules on tip; endopod broad, apically rounded, fringed with fine setae. Description of figured males (Figs 17G, H, 18–23): Body (Fig. 17 G–H, 18A–B) length 4–4.3 mm; length 7.1 times largest width (excluding spines), width of pereonites subparallel. Pattern of spination as in females, spines smaller than in females; spines knob-like. Head fused to pereonite 1, suture absent. Eyes prominent, bulbous. Pereonite 1 lateral margin deep, convex. Pereonite 2 short, 0.4 times length of pereonite 4. Pereonite 3 short, 0.4 times length of pereonite 4. Pereonite 4 0.2 time body length; mid- and anterior parts constricted, anterior transverse spine row absent. Pereonite 5 0.4 times length of pereonite 4. Pereonite 6 0.39 times length of pereonite 4. Pereonite 7 0.3 times length of pereonite 4. All pleonites fused into pleotelson, only one pleonite barely visible. Pleotelson with different pattern of spines from that of pereonites; pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with few small spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of pleotelson flat tipped and slightly dorsally orientated. Antennula (Figs 18C, D, 19A) flagellum article 1 short, fine seta distally, article 2 4.3 times longer that article 1, 4.5 times longer than wide, with 14 aesthetascs on distal and lateral margin. Antenna (Fig. 19B) peduncle with 5 articles, articles 4 and 5 longest; flagellum 0.5 times penduncle article 5, flagellum with 3 articles and claw; flagellum with fine setae. Article 2 0.6 length times article 1 length; article 3 0.5 times article 1; claw 1.1 times article 3. Labrum (Fig. 19C) with fine setae. Right mandible (Fig. 19D) molar smooth, lacinia mobilis with 3 major lobes and several irregular smaller lobes. Spine row comprising 2 dentate spines. Incisor 3-lobed. Left mandible (Fig. 19E) molar smooth, but slightly dentate on anterior edge. Lacinia mobilis 3-lobed. Spine row comprising 3 dentate spines. Incisor 2-lobed. Maxillula (Fig. 19F) lateral lobe with 11 cuspidate apical setae and 1 pappose seta (mesial lobe got lost during disection). Maxilla (Fig. 19G) mesial lobe oblique margin with 5 robust pappose setae, 5 long, simple setae on anterior edge; middle lobe with 2 long papposerrate setae; lateral lobe with 2 long papposerrate setae. Maxilliped (Figs 19H, 20A) endite ventrally with 1 slender setulate seta; distally with several pappose setae; 2 coupling hooks. Palp article 1 short; article 2 with several long setulate setae mesiodistally and ventrally; article 3 longest palp article, with long, slender setulate setae distally and on ventral surface; articles 4 and 5 distally with several long setulate setae. Epipodite distally rounded. Pereopod 1 (Fig. 20B) held close to mouthparts; ischium short, several long simple setae on inferior margin and distally on ischium; merus short, 1.2 times longer than wide, several long simple setae on inferior margin, 2 pectinate setae distally on superior margin; carpus 1.9 times longer than wide, length 1.6 times merus length, inferior margin with long slender papposerrate setae; propodus length 1.1 times carpus length, 2 times longer than wide, several slender papposerrate setae on inferior margin, denticulate setae distally on superior margin; dactylus short, 0.2 times propodus length, distally with 4 long simple setae, unguis absent. Pereopod 2 (Fig. 21A) basis short, inferior margin with several slender setae and 3 penicillate setae on superior margin; ischium short, inferior margin with several slender simple setae; merus-propodus long and narrow; merus long, 2.5 times longer than wide, groups of long, slender simple setae on inferior margin; carpus long, 3.9 times longer than wide, length 1.4 times merus length, groups of long, slender simple setae on inferior margin; propodus long, 4.4 times longer than wide, length 0.9 times carpus length, groups of long, slender simple setae on inferior margin; dactylus short, slender, length 0.1 times propodus length, unguis present, but broken. Pereopods 3 and 4 (Fig. 21B, C) similar to pereopod 2. Pereopods 5–7 (Fig. 22 A–C) similar in shape, stout, with sparse setae; basis of pereopods 5 to 6 with prominent spine and 3 penicillate setae. Pereopod 7 basis without spine, with 4 penicillate setae; carpus and merus similar in length, propodus 1.9 to 2.3 times longer than carpus, 1.8–1.9 times longer than dactylus. Dactylus with 2 ungui, secondary unguis robust (Fig. 18E). Penial plate (Fig. 23G) slightly turned, simple. Pleopod 1 (Fig. 23B) peduncle 2.5 times longer than wide, with 3 coupling hooks; endopod distally with 6 apical plumose setae; expod as long as endopod, distally with 6 apical plumose setae. Pleopod 2 (Fig. 23C) with 2 coupling hooks; endopod with 4 apical plumose setae, exopod with 7 apical plumose setae; appendix masculina styliform, straight, 1.7 times longer than endopod. Pleopods 3–5 (Fig. 23 D–F) with expanded exo- and endopods; rami apically rounded; 2 plumose setae on endopod of pleopod 3; 1 plumose seta on endopod of pleopods 4 and 5. Uropod (Fig. 23A) rounded anteriorly, tapering posteriorly; exopod 0.3 times endopod length, 2 apical setae with plumose shaft and short setules on tip; endopod broad, apically rounded, fringed with fine setae. Remarks: Schultz (1981) erected Spectrarcturus Schultz, 1981 for a new species, Spectrarcturus multispinatus. The holotype is damaged, which according to Schultz, referencing Richardson (1905), looked much like Pleuroprion murdochi (Benedict, 1898). The description of Spectrarcturus multispinatus is somewhat inaccurate. Schultz (1981: fig. 2A, C) showed a single transverse row of spines on pereonite 4, whereas our re-examination demonstrated that pereonite 4 is actually longer and has two rows of spines (Fig. 25). This inaccuracy could be because the only available specimen was damaged on the left side, as stated by Schultz (1981). No characters used in Schultz´s (1981) description of S. multispinatus separate this species convincingly from P. murdochi. We therefore treat S. multispinatus as a subjective junior synonym and transfer both names to Spectrarcturus. Spectrarcturus murdochi comb. nov. shows pronounced sexual dimorphism in body shape and in size. Males are considerably smaller than females, and with fewer spines on the body. Pereonite 4 has similar proportion of the total body length in both sexes, but the length ratio between pereonite 4 and pereonites 3–5 differs between sexes. The pleotelson of females is posteriorly bifid, while it is flat tipped in the males. Females vary in the pattern of the mesial spines in the second row of spines on pereonite 4. Females have either one pair of simple, large posteromesial spines (Fig. 17A, B), a pair of forked spines (Fig. 17C, D), or a forked spine on one side but simple spine on the other side (Fig. 17A, B). Kussakin (1982) observed vari

Pleuroprion zur Strassen, 1903 is revised and restricted to its type species, Antares chuni zur Strassen, 1902, which is redescribed, using the type material from the German Deep-Sea Expedition in 1898–1899 and more recent material. Pleuroprion is transferred to Holidoteidae Wägele, 1989. Pleuroprion frigidum Hansen, 1916 is transferred to Astacilla Cordiner, 1793 (Arcturidae), while all other species previously placed in Pleuroprion, i.e. P. murdochi (Benedict, 1898), P. chlebovitschi Kussakin, 1972, P. fabulosum Gujanova, 1955, P. furcatum Kussakin, 1982, P. hystrix (Sars, 1877), P. intermedium (Richardson, 1899), P. iturupicum Kussakin & Mezhov, 1979 and P. toporoki Kussakin, 1972, are transferred to Spectrarcturus Schultz, 1981 (Arcturidae). The type species of Spectrarcturus, S. multispinatus Schultz, 1981, is a subjective junior synonym of Arcturus murdochi Benedict, 1898, now S. murdochi comb. nov. Spectrarcturus murdochi (Benedict, 1898) is redescribed on the basis of its type material and new material from South Greenland.

Spectrarcturus toporoki (Kussakin, 1972) comb. nov. (Fig. 33) Pleuroprion toporoki Kussakin, 1972: 186–189, figs 5–6. — Kussakin, 1982: 432–435, figs 321–322. Material examined: Paratype female, ZIN RAS cat. no. 2/49344, Kobjakova R / V “Toporok”, station 46, 6 September 1948, South Kurile Islands, Ituruo Island. Diagnosis: Body with numerous large and small, robust, bluntly pointed spines; pereonite 4 0.18 times body length; evenly wide, sligthly longer than second and third together; pleotelson short, with several short spines, posterior margin rounded. All pleonites fused into pleotelson, only one pleonite visible. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna considerably shorter than body; short, robust. Spines on basis of pereopods 5 to 7. Oostegites present on pereopod 5, as small lobes. Male penis lanceolate, tapering evenly towards rounded distal end; appendix masculina long, distally curved, extending one-third of length beyond exopod. Distribution: Kurile Islands, at depths between 5 and 60 m (Kussakin 1972, 1982).

Genus Pleuroprion zur Strassen, 1903 Antares zur Strassen, 1902: 687–688 (preoccupied). Pleuroprion.—zur Strassen, 1903: 31 (replacement name).— Richardson, 1905: 342, key to species.— Stebbing 1908: 51–52.— Barnard, 1914: 216.— Hansen, 1916: 193–194, key to species.— Gurjanova, 1933: 160.— Gurjanova, 1936: 197–198, key to species.— Kensley, 1978: 33.— Kussakin, 1982: 420–421, key to species.— Wägele, 1989: 138–139.— Poore, 2001: 224.— Poore, 2015: 14. Diagnosis: Body flattened, with subparallel pereonites, pereonite 1 separated from head by shallow transverse groove, lateral margins of head and pereonite 1 shallow, convex. Pleonite 1 articulating with pleotelson, its posterior dorsal margin clearly indicated. Pleonite 2 of male dorsally doomed. Eyes prominent, bulbous. Antenna 2 flagellum of 2 articles plus claw. Maxillipedal palp article 3 not mesially lobed, about 1.5 times as wide as article 4. Pereopod 1 dactylus with unguis. Pereopods 2–4 with carpus longer than ischium and merus together; carpus and propodus tapering; fringed with long, pappose setae and some single simple setae on inferior margin; dactylus slender, unguis less than half length of body of dactylus, total 0.6 times propodus. Uropod biramous; exopod with terminal robust seta; endopod shorter than wide, with terminal stout seta. Penial plate tapering, apically bifid. Pleopod 1 of male exopod with 13 lateral plumose setae, with 9 distomesial plumose setae, with strong groove on its posterior face opening on short distolateral lobe; endopod shorter than exopod. Pleopod 2 with styliform appendix masculina, slightly longer than endopod. Oostegites unknown. Type species: Antares chuni zur Strassen, 1902. Included species: Pleuroprion chuni (zur Strassen, 1902). Remarks: Zur Strassen (1902) described a new species collected off South Africa and placed it in a new genus Antares. However, Antares was preoccupided and zur Strassen (1903) replaced it with Pleuroprion zur Strassen, 1903. Zur Strassen (1902, 1903) did not provide a generic diagnosis but distinguished it from Antarcturus zur Strassen, 1902, by the shape and spination of the head, size, shape and fusion of the first pereonite with the head without a clear suture, the epimera not distinct from the pereonites, and pleonite 1 articulating with the pleotelson. He noticed the difference in the shape of the fourth pereonite between Pleuroprion and other „arcturids“ s.l., and found the body of Pleuroprion to be more asellote-like than arcturid-like. Richardson (1905) provided a short diagnosis of Pleuroprion without consulting type material and added no detail. She included two species, Arcturus murdochi Benedict, 1898, and A. intermedius Richardson, 1899a, without discussion. Hansen (1916) found Pleuroprion closely allied to Arcturus Latreille, 1829, and moved Arcturus hystrix G.O. Sars, 1877, to Pleuroprion and described a new species, Pleuroprion frigidum Hansen, 1916. Neither author discussed Pleuroprion chuni. Kussakin (1982) found Pleuroprion intermediate between Neastacilla Tattersall, 1921, and Idarcturus Barnard, 1914b, though by some characters being close to Arcturus. Wägele (1989) suggested that Pleuroprion (as then diagnosed) belonged to an early branch of Arcturinae (now partly Antarcturidae), since their body was similar to those of the Pseudidotheinae. Wägele (1989) stated that isopod does not geniculate between pereonites 4 and 5. The simple, undifferentiated ungues of the pereopods would also support the suggestion of Wägele (1989) that these are primitive antarcturids. Later, Poore (2001) placed the genus within Antarcturidae. Pleuroprion, as now defined and containing only the type species, Pleuroprion chuni, is clearly a member of Holidoteidae, possessing a body without geniculation between pereonites 4 and 5, an apically bifid and splayed penial plate, both uropodal rami with a robust terminal seta and the uropodal exopod shorter than wide. Pleuroprion resembles Austroarcturus and differs from the other genera, Neoarcturus and Holidotea, in having a suture between the first and second pleonites and in having pereopods 2–4 fringed with dense pappose setae along the posterior margin. Pleuroprion differs from Holidotea and Austroarcturus in the narrower maxilliped palp, shorter terminal grooved lobe of the male pleopod 1 endopod, in ratio of the lengths of the rami of male pleopod 1, and in the relatively longer appendix masculina. Pleuroprion differs from Neoarcturus in having tergites of pereonite 1 to pleotelson well developed, the posterior ventral margin of pereonite 4 not notched in the male, by having several setae along pereopods 2–4 carpus and propodus and the ungues of pereopods 2–4 being shorter than the body of dactylus.

Spectrarcturus furcatus (Kussakin, 1982) comb. nov. (Fig. 28) Pleuroprion furcatum Kussakin, 1982: 430–432, figs 319–320. Material examined: Holotype female, ZIN RAS cat. no. 1/63644, station 3013, 24 July 1959, R / V Pervenets, Bering Sea. Diagnosis: Body densely setose, with slender, bluntly pointed spines; head with anteriorly with middorsal spine, posterior row of spines across head; row of spines across pereonite 1; pereonites 2 and 3 with row of spines across pereonite; pereonite 4 with anterior and posterior row of spines across pereonite, pair of spines between rows; pereonite 4 0.2 times body length; trapezoid, 1.7 times longer than third pereonite. Pleotelson long, with few long spines anteriorly; lateral margins with spines; posterior part of pleotelson tapeing towards apex. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna long and slender, about 0.8 of total body length; with pronounced spine dorsally on third segment, spine near mid-laterally on fourth segment. Spines absent from basis of pereopods 5–7, small bump on basis of pereopod 6. Oostegites present at least on pereopod 4. Remarks: The species can be distinguished from other species of Spectrarcturus on the shape of the pleotelson and the configuration of the spines on the body. The male is not yet known. Distribution: Bering Sea, Northwest Pacific, at 255 m (Kussakin 1982).

Genus Spectrarcturus Schultz, 1981 Spectrarcturus Schultz, 1981: 67. Spectarcturus.— Poore, 2001: 222 (incorrect spelling). Diagnosis: Body cylindrical. Pereonite 1 fused to head, with shallow transverse groove on former suture line. Lateral margins of head and pereonite 1 margin deep, convex, embracing mouthparts and pereopod 1 laterally. Pereonite 4 longest, 2–4 times as long as pereonite 3. All pleonites fused with pleotelson, with at least 2 pairs of lateral wings. Antenna with large spines on peduncle articles 2 and 3; flagellum short, with 3 articles and 1 distal claw-like article in females; in males distal article spine-like. Pereopod 1 dactylus short, without unguis. Pereopods 2–4 not flexed between carpus and propodus, with paired long setae along lower margin; with small claw-like dactyli, with short unguis. Pereopods 5–7 dactyli with 2 ungues. Male pleopod 1 simple, exopod without diagonal groove. Type species: Spectrarcturus multispinatus Schultz, 1981 = S. murdochi (Benedict, 1898). Included species: Spectrarcturus murdochi (Benedict, 1898) comb. nov.; Spectrarcturus chlebovitschi (Kussakin, 1972) comb. nov.; Spectrarcturus fabulosus (Gurjanova, 1955) comb. nov.; Spectrarcturus furcatus (Kussakin, 1982) comb. nov.; Spectrarcturus hystrix (Sars, 1877) comb. nov.; Spectrarcturus intermedius (Richardson, 1899a) comb. nov.; Spectrarcturus iturupicus (Kussakin & Mezhov, 1979) comb. nov.; Spectrarcturus toporoki (Kussakin, 1972) comb. nov. Remarks: The genus falls within Arcturidae as diagnosed by Poore (2001). Spectrarcturus resembles mostly Arcturus Latreille, 1829, another genus largely confined to the Northern Hemisphere, with which it shares a lack of flexure between the carpus and propodus of pereopods 2–4. It differs in having a short antennal flagellum rather than multiarticulate as in Arcturus and absence of the dactylus on pereopod 1. Few species of Arcturus have lateral wings on the pleotelson (Kussakin 1982). All species occur in the Northern hemisphere, where six species (S. chlebovitschi, S. fabulosus, S. furcatus, S. intermedius, S. iturupicus and S. toporoki) occur in the northernmost North Pacific (Bering Sea, Kurile Islands, Aleutian Islands, Sea of Okhotsk), S. hystrix in the northernmost North Atlantic Ocean, and S. murdochi occurs widely in the North Pacific and in Arctic waters around Greenland. The latter species has not been reported in the high Arctic Ocean, between these regions. The centre of diversity is in the northernmost North Pacific. The species are mostly shallow water species (several occurring as shallow as 5 or 6 meters), allowing dispersal through the shallow Bering Strait (maximum depths of around 53 m). Bering Strait first opened near the end of the Miocene at 5.32 MYA (Gladenkov et al. 2002), but became later closed and reopened due to land-rise and glaciations, with the last opening about 11 cal ka BP (Jakobsson et al. 2017) and lasting until the present., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 14-15, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Schultz, G. A. (1981) Arcturidae from the Antarctic and Southern Seas (Isopoda, Valvifera) Part I. Antarctic Research Series, Biology of the Antarctic Seas, X, 32, 63 - 94. https: // doi. org / 10.1029 / AR 032 p 0063","Poore, G. C. B. (2001) Isopoda Valvifera: Diagnoses and relationships of the families. Journal of Crustacean Biology, 21, 205 - 230. https: // doi. org / 10.1163 / 20021975 - 99990118","Benedict, J. E. (1898) The Arcturidae of the United States National Museum. Proceedings of the Biological Society of Washington, 12, 41 - 51.","Kussakin, O. G. (1972) Isopoda from the coastal zone of the Kurile Islands. III. Three new arcturids from the Middle Kurils with taxonomic remarks on the family Arcturidae. Crustaceana, Supplement 3, 178 - 189.","Gurjanova, E. F. (1955) The isopod crustacean fauna (Isopoda) of the Pacific Ocean VI. New species of Valvifera from the Kurile-Sakhalin Region. Trudy Instituta Zoologii Akademia Nauk USSR, 21, 208 - 230. [in Russian]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Sars, G. O. (1877) Prodromus descriptionis crustaceorum et pycnogonidarum, quae in expeditione norvegica anno 1876 observavit. Archiv for Mathematik og Naturvidenskab, 2, 237 - 271.","Richardson, H. (1899 a) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Proceedings of the United States National Museum, 21 (1175), 815 - 869. https: // doi. org / 10.5479 / si. 00963801.21 - 1175.815","Kussakin, O. G. & Mezhov, B. V. (1979) Isopod Crustacea of the sublittoral and the upper bathyal zone of the Kurile Islands. In: Kussakin, O. G. (Ed.), Biology of the shelf of the Kurile Islands. Academy of Sciences, Far East Center, USSR, Moscow, pp. 125 - 199. [in Russian]","Latreille, P. A. (1829) Les Crustaces, les Arachnides et les Insectes, distribues en familles naturelles. In: Cuvier, G. (Ed.), Le Regne Animal distribue d'apres son organisation, pour servir de base a l'histoire naturelle des animaux et d'introduction a l'anatomie comparee. Nouvelle Edition, revue et augmentee. Deterville, Paris, pp. Xxvii + 1 - 584. https: // doi. org / 10.5962 / bhl. title. 11575","Gladenkov, A. Y., Oleinik, A. E., Marincovich, L. & Barinov, K. B. (2002) A refined age for the earliest opening of Bering Strait. Palaeogeograpy, Palaeoclimatology, Palaeoecology, 183, 321 - 328. https: // doi. org / 10.1016 / S 0031 - 0182 (02) 00249 - 3","Jakobsson, M., Pearce, C., Cronin, T. M., Backman, J., Anderson, L. G., Barrientos, N., Bjork, G., Coxall, H., de Boer, A., Mayer, L. A., Morth, C. - M., Nilsson, J., Rattray, J. E., Stranne, C., Semiletov, I. & O'Regan, M. (2017) Post-glacial flooding of the Bering Land Bridge dated to 11 cal ka BP based on new geophysical and sediment records. Climate of the Past, 13, 991 - 1005. https: // doi. org / 10.5194 / cp- 13 - 991 - 2017"]}

Spectrarcturus murdochi (Benedict, 1898) comb. nov. (Figs 9–25) Arcturus murdochi Benedict, 1898: 49–50, fig. 9. Pleuroprion murdochi.— Richardson, 1899a: 855.— Richardson, 1900: 230.— Richardson, 1905: 342–344, figs 371–372.— Hansen, 1916: 195–196.— Boone, 1920: 30.— Gurjanova, 1936, 198–200, fig. 127.— Gurjanova, 1952: 176.— Schultz, 1969: 52, fig. 53a.— Kussakin & Mezhov, 1979: 149.— Kussakin, 1982: 424–427, figs 315–316. Spectrarcturus multispinatus Schultz, 1981: 67, fig. 2A–I. Syn. nov. Material examined: Pleuroprion murdochi, holotype, female, 10.5 mm (12 mm according to Richardson 1905) (USNM 7915), Point Barrow Expedition, 31 August 1883, Point Franklin, Alaska. Spectrarcturus multispinatus, holotype, female, 10 mm length (9 mm according to Schultz 1981) (USNM 181264) (holotype extensively fouled with bacteria), Hero 3-290, Little Nellefiske Bank, Greenland, 64°54´N, 53°38´W, 18 August 1968, 79– 85 m. New material: Illustrated or dissected specimens. Female, 7.6 mm (ZMH 43165), WH244 Stn 2002-3 (SW station revisited), 60°00.18´N, 46°31.02´W, 167 m, 1 November 2002, sediment as in stn 2001-3, 4.44°C, salinity 34.03, 749 individuals; male, 4.3 mm (ZMH 43166), WH244 Stn 2002-3, same data as before; female, 6.8 mm (ZMH 43167), WH244 Stn 2002-3, same data as before; preparatory female, 6.0 mm (ZMH 43168), WH 233 Stn 2001-3 (SW station), 59°59.99´N, 46°30.83´W, 161 m, 19 October 2001, sandy bottoms, with few small stones and rich in macroinvertebrates (corals, crinoids, ophiuroids, sponges), 5.88°C, salinity 34.53, 847 individuals; preparatory female, 5.9 mm (ZMH 43169), WH244 Stn 2002-3, same data as before; female, 7.6 mm (ZMH 43170), WH 233 Stn 2001-3, same data as before; female, 7.5 mm (ZMH 43171), WH 233 Stn 2001-3, same data as before; juvenile (manca 2), 2.1 mm (ZMH 43172) WH244 Stn 2002-3, same data as before; juvenile (manca 3), 3.3 mm (ZMH 43173), WH244 Stn 2002-3, same data as before; male, 4.1 mm (ZMH 43174), WH244 Stn 2002-3, same data as before; female, 7.2 mm (ZMH 43175), WH244 Stn 2002-3, same data as before. Further material (not catalogued material, deposited at ZMH, UI and ZMB): WH 233 Stn 1013, 63°36´N, 37°41´W, 237 m, 24 October 2001, sediment consisting mostly of sand, corals, sponges and mussel shells, 4.34°C, salinity 34.86, 13 individuals; WH 233 Stn 1016, 63°34´N, 39°18´W, 219 m, 25 October 2001, sediment as in stn 1013, 4.37°C, salinity 34.81, 4 individuals; WH 233 Stn 1023, 62°28´N, 40°39´W, 251 m, 26 October 2001, sediment as in stn 1013, 4.68°C, salinity 34.48, 1 individual; WH 233 Stn 1047, 60°18´N, 46°35´W, 154 m, 31 October 2001, sediment pure sand, 5.53°C, salinity 34.52, 7 individuals; WH 233 Stn 2001-4 (NW station), 63°07.44´N, 52°17.50´W, 162 m, 6 November 2001, sandy bottoms, with few small stones and rich in macroinvertebrates (corals, crinoids, ophiuroids, sponges), 5.74°C, salinity 34.83, 2 individuals; WH 268 Stn 2004-3 (SW station revisited), 59°59.94´N, 46°31.05´W, 23 October 2004, 160 m, sediment as in stn 2001-3, 6.22°C, salinity 34.67, 349 individuals; WH 268 Stn 2004-4 (NW station revisited), 63°07.22´N, 52°16.84´W, 152 m, 28 October 2004, sediment as in stn 2001-4, 4.48°C, salinity 33.96, 12 individuals. This material was referred to as Spectrarcturus multispinatus in Stransky & Brandt (2010) and Stransky & Svavarsson (2010). Diagnosis: Body with several large, bluntly pointed spines; 8 spines in transverse row on pereonite 1; pereonite 2 with 6 spines in transverse row, laterodistal margin anterior knob where spines are found on latter pereonites; pereonite 3 with 6 spines in transverse row and small anterolateral and posterolateral spines; pereonite 4 trapezoid, 1.8–2.5 times longer than third pereonite, with anterior transverse spine row with 6 spines, smaller anterolateral spine and small lateral spine or fork spine posterior to spine row; posterior spine row with 6 spines; pereonite 5 with 6 spines in transverse row, small anterolateral and posterolateral spines; pereonite 6 with 6 spines in transverse row, small anterolateral and posterolateral spines; pereonite 7 with 6 spines in transverse row, small posterolateral spine. Pleotelson long, with pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with smaller spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of female pleotelson bifid and slightly dorsally orientated. All pleonites fused into pleotelson, only one pleonite visible. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna intermediate in length, about 0.6 of total body length; robust. Spines present on basis of pereopods 5–7. Oostegites present at pereopods 1–5. Redescription of figured females (Figs 9–17): Body (Figs 9A, B, 10A, B, 11 A–C) length 5.9–10.5 mm; length 4.5 times largest width (excluding spines), increasing in width towards pereonite 4, decreasing in width from pereonite 4 to pereonite 7. Fine setae covering body. Head fused to pereonite 1, suture absent, small ventral notch on lateral margin; small lateral spine near anterior margin, 3 spines dorsally and dorsolaterally between eyes, posterior end of head with 6 spines, dorsal pair largest. Eyes prominent, bulbous. Pereonite 1 lateral margin deep, convex; 8 spines in transverse row on pereonite 1, dorsal pair largest. Pereonite 2 short, 0.3 times length of pereonite 4, 6 spines in transverse row, dorsal pair largest, laterodistal margin with anterior knob where spines are found on latter pereonites. Pereonite 3 0.4 times length of pereonite 4, with 6 spines in transverse row and small anterolateral and posterolateral spines. Pereonite 4 0.2 times body length; anterior transverse spine row with 6 spines, smaller anterolateral spine and small lateral spine or fork spine (see variation) posterior to spine row; posterior spine row with 6 spines (see variation), dorsal pair largest on body. Pereonite 5 0.4 times length of pereonite 4, with 6 spines in transverse row, small anterolateral and posterolateral spines. Pereonite 6 0.4 times length of pereonite 4, with 6 spines in transverse row, small anterolateral and posterolateral spines. Pereonite 7 0.4 times length of pereonite 4, with 6 spines in transverse row, small posterolateral spine. All pleonites fused into pleotelson, only one pleonite visible. Pleotelson with different pattern of spines from that of pereonites; pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with smaller spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of pleotelson bifid and slightly dorsally orientated. Oostegites on pereopods 1 – 5, largest on pereopod 5 (Figs 9B, 10A, 11A, 17 E–F). Antennula (Fig. 12A) short, reaching little beyond distal end of second peduncular segment of antenna; peduncle article 1 wide and short, distally with 1 penicillate and 1 slender seta, article 2 0.5 times width of article 1, distally with 4 penicillate setae; flagellum article 1 short, fine seta distally, article 2 2.3 times longer that article 1, 4.4 times longer than wide, with 4–5 aesthetascs (sometimes 3) and 2 penicillate setae (1 broken off in illustration) distally. Antenna (Fig. 12B) peduncle with 5 articles, articles 4 and 5 longest; flagellum 0.5 times penduncle article 5, flagellum with 3 articles and claw (partly broken off); flagellum with fine setae (mostly broken off); article 2 0.5 length times article 1 length; article 3 0.2 times article 1. Labrum (Fig. 12C) with fine setae. Right mandible (Fig. 12D) molar smooth, slightly dentate on anterior edge. Lacinia mobilis with 2 major lobes and 3–4 smaller lobes; spine row comprising 2 dentate spines. Incisor 3-toothed. Left mandible (Fig. 12E) molar smooth, lacinia mobilis 2-lobed; spine row comprising 3 dentate spines, incisor 3-toothed. Maxillula (Fig. 12F) mesial lobe with 3 long pappose setae distally and mesially one pappose and several fine, slender setae; lateral lobe with 10 cuspidate apical setae and 1 smaller robust apical seta. Maxilla (Fig. 12G) mesial lobe oblique margin with 9 robust papposerrate setae, 12 – 13 long, simple setae on anterior edge; middle lobe with 3 long pectinate, finely setulate setae; lateral lobe with 2 long pectinate, finely setulate setae. Maxilliped (Fig. 12H) endite ventrally with 4 slender setae; distally with 7 pappose setae; 3 or 4 large coupling hooks. Palp article 1 short; article 2 with several long simple setae mesiodistally and ventrally; article 3 longest palp article, with long, slender simple setae distally and on ventral surface; articles 4 and 5 distally with several long simple setae. Epipodite distally rounded. Pereopod 1 (Fig. 13A) held close to mouthparts; basis with several long simple setae distally; ischium short, several long setae on inferior margin and distally on ischium; merus short, 0.88 times longer than wide, several long simple setae and 1 small penicillate seta on inferior margin and distally, superior margin distally with 2 pectinate setae (broken); carpus 2.03 times longer than wide, length 1.7 times merus length, inferior margin with row of clavate distally setulate setae and long slender setae inbetween; propodus length 1.0 times carpus length, 2.1 times longer than wide, several clavate distally setulate setae and slender setae on inferior margin, pectinate and denticulate setae distally on superior margin; dactylus short, 0.2 times propodus length, distally with 3 long setae (2 broken), unguis absent. Pereopod 2 (Fig. 13B) basis short, superior margin distally forming spine, inferior margin with several slender simple setae; ischium short, inferior margin with several slender simple setae; merus-propodus long and narrow; merus long, 2.7 times longer than wide, groups of long, slender simple setae on inferior margin; carpus long, 4.3 times longer than wide, length 1.2 times merus length, groups of slender, long simple setae on inferior margin; propodus long, 9 times longer than wide, length 1.1 times carpus length, groups of slender, long simple setae on inferior margin; dactylus short, slender, length 0.1 times propodus length, unguis present. Pereopods 3 and 4 (Fig. 14A, B) similar to pereopod 2; conspicious spine on superior margin of basis; coxa with 2 spines. Pereopods 5–7 (Fig. 15 A–C) similar in shape, stout, with sparse setae; basis with prominent spine; carpus and merus similar in length, propodus 2.1 to 2.5 times longer than carpus and 1.7 to 2.2 times longer than dactylus. Dactylus with 2 ungui, secondary unguis robust. Pleopod 1 (Fig. 16A) peduncle 3.5 times longer than wide, with 3 coupling hooks; endopod distally with 5 apical plumose setae; expod as long as endopod, distally with 4 apical plumose setae. Pleopod 2 (Fig. 16B) with 2 coupling hooks; endopod with 7 apical plumose setae, exopod with 10 apical plumose setae. Pleopods 3–5 (Fig. 16 C–E) with expanded exo- and endopods; rami apically rounded; 2 plumose setae on endopod of pleopod 3; 1 plumose seta on endopod of pleopods 4 and 5. Uropod (Fig. 15D) rounded anteriorly, tapering posteriorly with 1 plumose seta; exopod 0.4 times endopod length, 2 apical setae with plumose shaft and short setules on tip; endopod broad, apically rounded, fringed with fine setae. Description of figured males (Figs 17G, H, 18–23): Body (Fig. 17 G–H, 18A–B) length 4–4.3 mm; length 7.1 times largest width (excluding spines), width of pereonites subparallel. Pattern of spination as in females, spines smaller than in females; spines knob-like. Head fused to pereonite 1, suture absent. Eyes prominent, bulbous. Pereonite 1 lateral margin deep, convex. Pereonite 2 short, 0.4 times length of pereonite 4. Pereonite 3 short, 0.4 times length of pereonite 4. Pereonite 4 0.2 time body length; mid- and anterior parts constricted, anterior transverse spine row absent. Pereonite 5 0.4 times length of pereonite 4. Pereonite 6 0.39 times length of pereonite 4. Pereonite 7 0.3 times length of pereonite 4. All pleonites fused into pleotelson, only one pleonite barely visible. Pleotelson with different pattern of spines from that of pereonites; pair of three spines in row dorsally on anterior part of pleotelson, mid-dorsally pair of dorsal spines; posterior part with few small spines; spine laterally near anterior margin of pleotelson, pair of large lateral spines near ventral margin; posterior end of pleotelson flat tipped and slightly dorsally orientated. Antennula (Figs 18C, D, 19A) flagellum article 1 short, fine seta distally, article 2 4.3 times longer that article 1, 4.5 times longer than wide, with 14 aesthetascs on distal and lateral margin. Antenna (Fig. 19B) peduncle with 5 articles, articles 4 and 5 longest; flagellum 0.5 times penduncle article 5, flagellum with 3 articles and claw; flagellum with fine setae. Article 2 0.6 length times article 1 length; article 3 0.5 times article 1; claw 1.1 times article 3. Labrum (Fig. 19C) with fine setae. Right mandible (Fig. 19D) molar smooth, lacinia mobilis with 3 major lobes and several irregular smaller lobes. Spine row comprising 2 dentate spines. Incisor 3-lobed. Left mandible (Fig. 19E) molar smooth, but slightly dentate on anterior edge. Lacinia mobilis 3-lobed. Spine row comprising 3 dentate spines. Incisor 2-lobed. Maxillula (Fig. 19F) lateral lobe with 11 cuspidate apical setae and 1 pappose seta (mesial lobe got lost during disection). Maxilla (Fig. 19G) mesial lobe oblique margin with 5 robust pappose setae, 5 long, simple setae on anterior edge; middle lobe with 2 long papposerrate setae; lateral lobe with 2 long papposerrate setae. Maxilliped (Figs 19H, 20A) endite ventrally with 1 slender setulate seta; distally with several pappose setae; 2 coupling hooks. Palp article 1 short; article 2 with several long setulate setae mesiodistally and ventrally; article 3 longest palp article, with long, slender setulate setae distally and on ventral surface; articles 4 and 5 distally with several long setulate setae. Epipodite distally rounded. Pereopod 1 (Fig. 20B) held close to mouthparts; ischium short, several long simple setae on inferior margin and distally on ischium; merus short, 1.2 times longer than wide, several long simple setae on inferior margin, 2 pectinate setae distally on superior margin; carpus 1.9 times longer than wide, length 1.6 times merus length, inferior margin with long slender papposerrate setae; propodus length 1.1 times carpus length, 2 times longer than wide, several slender papposerrate setae on inferior margin, denticulate setae distally on superior margin; dactylus short, 0.2 times propodus length, distally with 4 long simple setae, unguis absent. Pereopod 2 (Fig. 21A) basis short, inferior margin with several slender setae and 3 penicillate setae on superior margin; ischium short, inferior margin with several slender simple setae; merus-propodus long and narrow; merus long, 2.5 times longer than wide, groups of long, slender simple setae on inferior margin; carpus long, 3.9 times longer than wide, length 1.4 times merus length, groups of long, slender simple setae on inferior margin; propodus long, 4.4 times longer than wide, length 0.9 times carpus length, groups of long, slender simple setae on inferior margin; dactylus short, slender, length 0.1 times propodus length, unguis present, but broken. Pereopods 3 and 4 (Fig. 21B, C) similar to pereopod 2. Pereopods 5–7 (Fig. 22 A–C) similar in shape, stout, with sparse setae; basis of pereopods 5 to 6 with prominent spine and 3 penicillate setae. Pereopod 7 basis without spine, with 4 penicillate setae; carpus and merus similar in length, propodus 1.9 to 2.3 times longer than carpus, 1.8–1.9 times longer than dactylus. Dactylus with 2 ungui, secondary unguis robust (Fig. 18E). Penial plate (Fig. 23G) slightly turned, simple. Pleopod 1 (Fig. 23B) peduncle 2.5 times longer than wide, with 3 coupling hooks; endopod distally with 6 apical plumose setae; expod as long as endopod, distally with 6 apical plumose setae. Pleopod 2 (Fig. 23C) with 2 coupling hooks; endopod with 4 apical plumose setae, exopod with 7 apical plumose setae; appendix masculina styliform, straight, 1.7 times longer than endopod. Pleopods 3–5 (Fig. 23 D–F) with expanded exo- and endopods; rami apically rounded; 2 plumose setae on endopod of pleopod 3; 1 plumose seta on endopod of pleopods 4 and 5. Uropod (Fig. 23A) rounded anteriorly, tapering posteriorly; exopod 0.3 times endopod length, 2 apical setae with plumose shaft and short setules on tip; endopod broad, apically rounded, fringed with fine setae. Remarks: Schultz (1981) erected Spectrarcturus Schultz, 1981 for a new species, Spectrarcturus multispinatus. The holotype is damaged, which according to Schultz, referencing Richardson (1905), looked much like Pleuroprion murdochi (Benedict, 1898). The description of Spectrarcturus multispinatus is somewhat inaccurate. Schultz (1981: fig. 2A, C) showed a single transverse row of spines on pereonite 4, whereas our re-examination demonstrated that pereonite 4 is actually longer and has two rows of spines (Fig. 25). This inaccuracy could be because the only available specimen was damaged on the left side, as stated by Schultz (1981). No characters used in Schultz´s (1981) description of S. multispinatus separate this species convincingly from P. murdochi. We therefore treat S. multispinatus as a subjective junior synonym and transfer both names to Spectrarcturus. Spectrarcturus murdochi comb. nov. shows pronounced sexual dimorphism in body shape and in size. Males are considerably smaller than females, and with fewer spines on the body. Pereonite 4 has similar proportion of the total body length in both sexes, but the length ratio between pereonite 4 and pereonites 3–5 differs between sexes. The pleotelson of females is posteriorly bifid, while it is flat tipped in the males. Females vary in the pattern of the mesial spines in the second row of spines on pereonite 4. Females have either one pair of simple, large posteromesial spines (Fig. 17A, B), a pair of forked spines (Fig. 17C, D), or a forked spine on one side but simple spine on the other side (Fig. 17A, B). Kussakin (1982) observed vari, Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 15-35, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Benedict, J. E. (1898) The Arcturidae of the United States National Museum. Proceedings of the Biological Society of Washington, 12, 41 - 51.","Richardson, H. (1899 a) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Proceedings of the United States National Museum, 21 (1175), 815 - 869. https: // doi. org / 10.5479 / si. 00963801.21 - 1175.815","Richardson, H. (1900) Synopses of North-American Invertebrates. 8. The Isopoda. American Naturalist, 34, 207 - 230 + 295 - 309. https: // doi. org / 10.1086 / 277619","Richardson, H. (1905) A monograph on the isopods of North America. Bulletin of the United States National Museum, 54, I-Liii + 1 - 727. https: // doi. org / 10.5479 / si. 03629236.54. i","Hansen, H. J. (1916) Crustacea Malacostraca III, Isopoda. The Danish Ingolf Expedition, 3 (5), 1 - 262.","Boone, P. L. (1920) The Isopoda of the Canadian Arctic and adjoining regions. Report of the Canadian Arctic Expedition 1913 - 1918, 7 (D), 3 - 40.","Gurjanova, E. F. (1936) Isopodes des Mers Orienalis. Fauna de L'URSS, Crustacees, 7 (3), i-XII + 1 - 279. [in Russian, Summary in German]","Gurjanova, E. F. (1952) Crustacea-Malacostraca of the Chukchi Sea and the Bering Strait - Extreme northeast of the USSR. II. Fauna and flora of the Chukchi Sea. Leningrad, Academy of Sciences of the USSR, pp. 169 - 215. [in Russian]","Schultz, G. A. (1969) How to know the marine isopod crustaceans. W. M. C. Brown Company Publishers, Dubuque, Iowa, 359 pp.","Kussakin, O. G. & Mezhov, B. V. (1979) Isopod Crustacea of the sublittoral and the upper bathyal zone of the Kurile Islands. In: Kussakin, O. G. (Ed.), Biology of the shelf of the Kurile Islands. Academy of Sciences, Far East Center, USSR, Moscow, pp. 125 - 199. [in Russian]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Schultz, G. A. (1981) Arcturidae from the Antarctic and Southern Seas (Isopoda, Valvifera) Part I. Antarctic Research Series, Biology of the Antarctic Seas, X, 32, 63 - 94. https: // doi. org / 10.1029 / AR 032 p 0063","Stransky, B. & Brandt, A. (2010) Occurrence, diversity and community structures of peracarid crustaceans (Crustacea, Malacos- traca) along the southern shelf of Greenland. Polar Biology, 33, 851 - 867. https: // doi. org / 10.1007 / s 00300 - 010 - 0785 - 0","Stransky, B. & Svavarsson, J. (2010) Diversity and species composition of peracarids (Crustacea: Malacostraca) on the South Greenland shelf: spatial and temporal variation. Polar Biology, 33, 125 - 139. https: // doi. org / 10.1007 / s 00300 - 009 - 0691 - 5"]}

Spectrarcturus fabulosus (Gurjanova, 1955) comb. nov. (Fig. 27) Pleuroprion fabulosus Gurjanova, 1955: 225–228, figs 13–14. Pleuroprion fabulosum.— Kussakin & Mezhov, 1979: 149.— Kussakin, 1982: 440–444, figs 327–329.— Kussakin & Vasina, 1990: 50–51, figs 3–4. Material examined: Paratype female, ZIN RAS cat. no. 3/22841, Kobjakova R / V “Toporok“, station 101, 14 September 1949, South Kurile Islands. Diagnosis: Body densely setose, with many slender, pointed spines, pair on each pereonite near midline of body, two pairs on pereonite 4; dorsolaterally single large spine and laterally additional spine on anterior pereonites; pereonite 4 0.2 times body length; trapezoid, 2 times longer than third pereonite. Pleotelson long, with few long spines anteriorly, lateral margins with spines, posterior part of pleotelson tapering towards apex. Antennula somewhat long, reaching about one third of length of third peduncular segment of antenna. Antenna long, slender, about 0.9 of total body length; pronounced spine mid-dorsally on second segment, spine distolaterally on fourth segment. Spines present on basis of pereopods 5–7. Oostegites present on pereopods 1–5, very small oostegite lobe on pereopod 5. Remarks: This species can be distinguished from the other species of Spectrarcturus on the dense setae of the body (also known in S. furcatus), the relatively long antennula and the narrowly pointed pleotelson, having only dorsal spines on the anterior most part of the pleotelson. The male is unknown. Distribution: Sea of Okhotsk, 385–414 m (Kussakin 1982; Kussakin & Vasina 1990).

Genus Pleuroprion zur Strassen, 1903 Antares zur Strassen, 1902: 687–688 (preoccupied). Pleuroprion.—zur Strassen, 1903: 31 (replacement name).— Richardson, 1905: 342, key to species.— Stebbing 1908: 51–52.— Barnard, 1914: 216.— Hansen, 1916: 193–194, key to species.— Gurjanova, 1933: 160.— Gurjanova, 1936: 197–198, key to species.— Kensley, 1978: 33.— Kussakin, 1982: 420–421, key to species.— Wägele, 1989: 138–139.— Poore, 2001: 224.— Poore, 2015: 14. Diagnosis: Body flattened, with subparallel pereonites, pereonite 1 separated from head by shallow transverse groove, lateral margins of head and pereonite 1 shallow, convex. Pleonite 1 articulating with pleotelson, its posterior dorsal margin clearly indicated. Pleonite 2 of male dorsally doomed. Eyes prominent, bulbous. Antenna 2 flagellum of 2 articles plus claw. Maxillipedal palp article 3 not mesially lobed, about 1.5 times as wide as article 4. Pereopod 1 dactylus with unguis. Pereopods 2–4 with carpus longer than ischium and merus together; carpus and propodus tapering; fringed with long, pappose setae and some single simple setae on inferior margin; dactylus slender, unguis less than half length of body of dactylus, total 0.6 times propodus. Uropod biramous; exopod with terminal robust seta; endopod shorter than wide, with terminal stout seta. Penial plate tapering, apically bifid. Pleopod 1 of male exopod with 13 lateral plumose setae, with 9 distomesial plumose setae, with strong groove on its posterior face opening on short distolateral lobe; endopod shorter than exopod. Pleopod 2 with styliform appendix masculina, slightly longer than endopod. Oostegites unknown. Type species: Antares chuni zur Strassen, 1902. Included species: Pleuroprion chuni (zur Strassen, 1902). Remarks: Zur Strassen (1902) described a new species collected off South Africa and placed it in a new genus Antares. However, Antares was preoccupided and zur Strassen (1903) replaced it with Pleuroprion zur Strassen, 1903. Zur Strassen (1902, 1903) did not provide a generic diagnosis but distinguished it from Antarcturus zur Strassen, 1902, by the shape and spination of the head, size, shape and fusion of the first pereonite with the head without a clear suture, the epimera not distinct from the pereonites, and pleonite 1 articulating with the pleotelson. He noticed the difference in the shape of the fourth pereonite between Pleuroprion and other „arcturids“ s.l., and found the body of Pleuroprion to be more asellote-like than arcturid-like. Richardson (1905) provided a short diagnosis of Pleuroprion without consulting type material and added no detail. She included two species, Arcturus murdochi Benedict, 1898, and A. intermedius Richardson, 1899a, without discussion. Hansen (1916) found Pleuroprion closely allied to Arcturus Latreille, 1829, and moved Arcturus hystrix G.O. Sars, 1877, to Pleuroprion and described a new species, Pleuroprion frigidum Hansen, 1916. Neither author discussed Pleuroprion chuni. Kussakin (1982) found Pleuroprion intermediate between Neastacilla Tattersall, 1921, and Idarcturus Barnard, 1914b, though by some characters being close to Arcturus. Wägele (1989) suggested that Pleuroprion (as then diagnosed) belonged to an early branch of Arcturinae (now partly Antarcturidae), since their body was similar to those of the Pseudidotheinae. Wägele (1989) stated that isopod does not geniculate between pereonites 4 and 5. The simple, undifferentiated ungues of the pereopods would also support the suggestion of Wägele (1989) that these are primitive antarcturids. Later, Poore (2001) placed the genus within Antarcturidae. Pleuroprion, as now defined and containing only the type species, Pleuroprion chuni, is clearly a member of Holidoteidae, possessing a body without geniculation between pereonites 4 and 5, an apically bifid and splayed penial plate, both uropodal rami with a robust terminal seta and the uropodal exopod shorter than wide. Pleuroprion resembles Austroarcturus and differs from the other genera, Neoarcturus and Holidotea, in having a suture between the first and second pleonites and in having pereopods 2–4 fringed with dense pappose setae along the posterior margin. Pleuroprion differs from Holidotea and Austroarcturus in the narrower maxilliped palp, shorter terminal grooved lobe of the male pleopod 1 endopod, in ratio of the lengths of the rami of male pleopod 1, and in the relatively longer appendix masculina. Pleuroprion differs from Neoarcturus in having tergites of pereonite 1 to pleotelson well developed, the posterior ventral margin of pereonite 4 not notched in the male, by having several setae along pereopods 2–4 carpus and propodus and the ungues of pereopods 2–4 being shorter than the body of dactylus., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 3-4, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Richardson, H. (1905) A monograph on the isopods of North America. Bulletin of the United States National Museum, 54, I-Liii + 1 - 727. https: // doi. org / 10.5479 / si. 03629236.54. i","Stebbing, T. R. R. (1908) South African Crustacea. Part IV. Annals of the South African Museum, 6, 1 - 96, plates I-XV. https: // doi. org / 10.5962 / bhl. part. 15553","Hansen, H. J. (1916) Crustacea Malacostraca III, Isopoda. The Danish Ingolf Expedition, 3 (5), 1 - 262.","Gurjanova, E. F. (1933) Les isopodes des mers arctiques. Fauna Arctica, 6 (5), 391 - 470.","Gurjanova, E. F. (1936) Isopodes des Mers Orienalis. Fauna de L'URSS, Crustacees, 7 (3), i-XII + 1 - 279. [in Russian, Summary in German]","Kensley, B. (1978) Guide to the marine isopods of Southern Africa. Trustees of the South African Museum, Cape Town, 173 pp.","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Wagele, J. W. (1989) Evolution und phylogenetisches System der Isopoda. Stand der Forschung und neue Erkenntnisse. Zoologica, Stuttgart, 140, 1 - 262.","Poore, G. C. B. (2001) Isopoda Valvifera: Diagnoses and relationships of the families. Journal of Crustacean Biology, 21, 205 - 230. https: // doi. org / 10.1163 / 20021975 - 99990118","Poore, G. C. B. (2015) Halearcturus, a new genus of Antarcturidae Poore, 2001 (Crustacea: Isopoda: Valvifera) with a key to genera of the family. Memoirs of Museum of Victoria, 73, 13 - 18. https: // doi. org / 10.24199 / j. mmv. 2015.73.02","Benedict, J. E. (1898) The Arcturidae of the United States National Museum. Proceedings of the Biological Society of Washington, 12, 41 - 51.","Richardson, H. (1899 a) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Proceedings of the United States National Museum, 21 (1175), 815 - 869. https: // doi. org / 10.5479 / si. 00963801.21 - 1175.815","Latreille, P. A. (1829) Les Crustaces, les Arachnides et les Insectes, distribues en familles naturelles. In: Cuvier, G. (Ed.), Le Regne Animal distribue d'apres son organisation, pour servir de base a l'histoire naturelle des animaux et d'introduction a l'anatomie comparee. Nouvelle Edition, revue et augmentee. Deterville, Paris, pp. Xxvii + 1 - 584. https: // doi. org / 10.5962 / bhl. title. 11575","Sars, G. O. (1877) Prodromus descriptionis crustaceorum et pycnogonidarum, quae in expeditione norvegica anno 1876 observavit. Archiv for Mathematik og Naturvidenskab, 2, 237 - 271.","Tattersall, W. M. (1921) Crustacea. Part VI. - Tanaidacea and Isopoda. British Antarctic (\" Terra Nova \") Expedition, Natural History Reports. Zoology, 3, 191 - 258, pls. 1 - 11.","Barnard, K. H. (1914 b) Contributions to the crustacean fauna of South Africa. 3. Additions to the marine Isopoda, with notes on some previously incompletely known species. Annals of the South African Museum, 10 (11), 325 - 358 a, 359 - 440. https: // doi. org / 10.5962 / bhl. part. 9319"]}

Spectrarcturus hystrix (Sars, 1877) comb. nov. (Figs 29–30) Arcturus hystrix Sars, 1877: 250–251 (erroneously labelled 350–351).— Sars, 1885: 104–106, pl. IX, figs 23–26.— Norman, 1904: 446. Pleuroprion hystrix. — Hansen, 1916: 194–195, pl. XV, fig. 6a–b.— Gurjanova, 1936: 200, fig. 128.— Kussakin, 1982: 421–424, figs 313–314. Material examined: Syntypes, F1683, Norwegian North-Atlantic Expedition 1876–1878, stations 18, 124, 164, 4 females. Other material. Female, WH 233, stn. 1023; male, Voucher 52975, POS 456 IceAGE 2, stn. 873-6 EBS from DZMB 43.916. Diagnosis: Body with several long and slender, bluntly pointed spines; pair on anterior part of head; posteriorly row of spines across head; pereonite 1 with row of spines across pereonite; pereonites 2 and 3 with row of spines across pereonites; two rows of spines on pereonite 4; pereonite 4 0.2 times body length; trapezoid, 2.1 times longer than third pereonite. Pleotelson intermediate in length, with 5 pairs of long and slender spines near midline of pleotelson, lateral margins with spines; posterior part of pleotelson tapering towards bifid apex; pleotelson upturned distally. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna short, about 0.6 of total body length; slender, with 3 large spines on second segment; large spine laterodistally on third segment, spine laterodistally on fourth segment. Spines present on basis of pereopods 5–7. Oostegites present on pereopod 1–5. Male smaller than female. Pattern of spination as in females, spines smaller than in females and more robust; middle part of pereonite 4 narrow, without spines. Posterior part of pleotelson tapering towards bifid apex; cleft of apex not as pronounced an in females. Endo- and exopod fringed with fine setae, distally with plumose setae; endopod with 7 setae; exopod with 11 setae; endopod slightly longer than exopod; pleopod 2 appendix masculina long and curved in distal half, about 1/3 longer than expodite, fringed with fine setae. Remarks: The species differs from all other Spectrarcturus species in the pattern of spination of the body. Other characteristics are the shape of the pleotelson and the long distolateral spine on article 3 of the antenna. Distribution: Northernmost North Atlantic, Nordic Seas: the Faeroe Islands, Norway, Greenland, at depths between 600–1150 m (Hansen 1916)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 37-42, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Sars, G. O. (1877) Prodromus descriptionis crustaceorum et pycnogonidarum, quae in expeditione norvegica anno 1876 observavit. Archiv for Mathematik og Naturvidenskab, 2, 237 - 271.","Sars, G. O. (1885) Den Norske Nordhavs-expedition, 1876 - 1878. Vol. 6. Zoology, Crustacea, 1, 1 - 280.","Norman, A. M. (1904) British Isopoda of the families Aegidae, Cirolanidae, Idoteidae, and Arcturidae. Annals and Magazine of Natural History, Series 7, 14, 430 - 450. https: // doi. org / 10.1080 / 03745480409443033","Hansen, H. J. (1916) Crustacea Malacostraca III, Isopoda. The Danish Ingolf Expedition, 3 (5), 1 - 262.","Gurjanova, E. F. (1936) Isopodes des Mers Orienalis. Fauna de L'URSS, Crustacees, 7 (3), i-XII + 1 - 279. [in Russian, Summary in German]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Gurjanova, E. F. (1955) The isopod crustacean fauna (Isopoda) of the Pacific Ocean VI. New species of Valvifera from the Kurile-Sakhalin Region. Trudy Instituta Zoologii Akademia Nauk USSR, 21, 208 - 230. [in Russian]"]}

Spectrarcturus iturupicus (Kussakin & Mezhov, 1979) comb. nov. (Fig. 32) Pleuroprion iturupicum Kussakin & Mezhov, 1979: 145–148, figs 3–4. — Kussakin, 1982: 435–437, figs 323–324. Material examined: Paratype female, ZIN RAS cat. no. 3/49358, station 44, South Kurile Islands, Iturup Island. Diagnosis: Body with numerous small tubercles; mid-dorsally pair of somewhat longer, robust spines; pereonite 4 0.18 times body length; posteriorly narrow, twice as long as second and third together. Pleotelson short, with numerous small tubercles and pairs of short spines, posterior margin rounded, large lateral spine near ventral margin. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna short and robust, about 0.6 of total body length. Spines on basis of pereopods 5 to 7. Oostegites present on pereopod 5, as small lobes. Remarks: Detailed examination of the mouthparts, the pleopods and the uropods was not possible. Kussakin & Mezhov (1979) provided only illustrations of the lateral view of the habitus, first antenna, maxilliped and pereopods 1, 2 and 7. The same illustrations were provided by Kussakin (1982). From Kussakin & Mezhov (1979) and our observations it is clear that the species fits well into Spectrarcturus. The species can be distinguished from other species of Spectrarcturus on the body shape, the numerous small tubercles on the body and the shape of the pleotelson. The male is not known. Distribution: Kurile Islands, at depth between 125–146 m (Kussakin & Mezhov 1979).

Spectrarcturus furcatus (Kussakin, 1982) comb. nov. (Fig. 28) Pleuroprion furcatum Kussakin, 1982: 430–432, figs 319–320. Material examined: Holotype female, ZIN RAS cat. no. 1/63644, station 3013, 24 July 1959, R / V Pervenets, Bering Sea. Diagnosis: Body densely setose, with slender, bluntly pointed spines; head with anteriorly with middorsal spine, posterior row of spines across head; row of spines across pereonite 1; pereonites 2 and 3 with row of spines across pereonite; pereonite 4 with anterior and posterior row of spines across pereonite, pair of spines between rows; pereonite 4 0.2 times body length; trapezoid, 1.7 times longer than third pereonite. Pleotelson long, with few long spines anteriorly; lateral margins with spines; posterior part of pleotelson tapeing towards apex. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna long and slender, about 0.8 of total body length; with pronounced spine dorsally on third segment, spine near mid-laterally on fourth segment. Spines absent from basis of pereopods 5–7, small bump on basis of pereopod 6. Oostegites present at least on pereopod 4. Remarks: The species can be distinguished from other species of Spectrarcturus on the shape of the pleotelson and the configuration of the spines on the body. The male is not yet known. Distribution: Bering Sea, Northwest Pacific, at 255 m (Kussakin 1982)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 37, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]"]}

Spectrarcturus intermedius (Richardson, 1899a) comb. nov. (Fig. 31) Arcturus intermedius Richardson, 1899a: 854–855.— Richardson, 1899b: 275–277. Pleuroprion intermedium. — Richardson, 1905: 344–346, fig. 373.— Gurjanova, 1936: 201, fig. 129.— Schultz, 1969: 52, fig. 53b.— Kussakin, 1982: 428–430, fig. 318. Material examined: Syntype, USMN 22581, Kyska Harbor, Aleutian Islands, 10 ftms, 1 female. Diagnosis: Body with numerous large, narrow, pointed spines; mid-dorsal spine anteriorly on head, mid-dorsally pair of spines on head, row of spines across pereonite 1; row of spines across pereonites 2 and 3; pereonite 4 0.2 times body length; trapezoid, about as long as second and third together; anterior and posterior rows of spines across pereonite 4, pair of spines middorsally. Pleotelson short, with several long and short spines on anterior part, one lateral spine on posterior part, posteriorly bifid apex, fork-like. Antennula short, not reaching distal end of second peduncular segment of antenna. Antenna long and slender, about 0.9 of total body length. Spines absent from basis of pereopods 5 to 7. Oostegites not present on pereopod 5. Remarks: The ventral lateral plate of the head has a deep incision at the anterior end of pereonite 1. The posterior end of the pleotelson ends in deep upraised fork, which distinguishes this species from all Spectrarcturus species, except S. hystrix and S. murdochi. The middorsal spine on anterior part of the head can be used to distinguish this species from several other Spectrarcturus species. Kussakin (1982) noted that the specimen occurring at the Commander Island differed from the holotype in the presence of a spine on article 3 and by having different shape of the body spines, but still considered that these specimens belonged to S. intermedium. Distribution: Western part of the Aleutian Islands, Kiska-Harbor Bay, Commander Island, at depths between 18–40 m (Kussakin 1982).

Spectrarcturus intermedius (Richardson, 1899a) comb. nov. (Fig. 31) Arcturus intermedius Richardson, 1899a: 854–855.— Richardson, 1899b: 275–277. Pleuroprion intermedium. — Richardson, 1905: 344–346, fig. 373.— Gurjanova, 1936: 201, fig. 129.— Schultz, 1969: 52, fig. 53b.— Kussakin, 1982: 428–430, fig. 318. Material examined: Syntype, USMN 22581, Kyska Harbor, Aleutian Islands, 10 ftms, 1 female. Diagnosis: Body with numerous large, narrow, pointed spines; mid-dorsal spine anteriorly on head, mid-dorsally pair of spines on head, row of spines across pereonite 1; row of spines across pereonites 2 and 3; pereonite 4 0.2 times body length; trapezoid, about as long as second and third together; anterior and posterior rows of spines across pereonite 4, pair of spines middorsally. Pleotelson short, with several long and short spines on anterior part, one lateral spine on posterior part, posteriorly bifid apex, fork-like. Antennula short, not reaching distal end of second peduncular segment of antenna. Antenna long and slender, about 0.9 of total body length. Spines absent from basis of pereopods 5 to 7. Oostegites not present on pereopod 5. Remarks: The ventral lateral plate of the head has a deep incision at the anterior end of pereonite 1. The posterior end of the pleotelson ends in deep upraised fork, which distinguishes this species from all Spectrarcturus species, except S. hystrix and S. murdochi. The middorsal spine on anterior part of the head can be used to distinguish this species from several other Spectrarcturus species. Kussakin (1982) noted that the specimen occurring at the Commander Island differed from the holotype in the presence of a spine on article 3 and by having different shape of the body spines, but still considered that these specimens belonged to S. intermedium. Distribution: Western part of the Aleutian Islands, Kiska-Harbor Bay, Commander Island, at depths between 18–40 m (Kussakin 1982)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 42, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Richardson, H. (1899 a) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Proceedings of the United States National Museum, 21 (1175), 815 - 869. https: // doi. org / 10.5479 / si. 00963801.21 - 1175.815","Richardson, H. (1899 b) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Annals and Magazine of Natural History, Series 7, 4 (21 - 23), 157 - 187, 260 - 277 & 321 - 338 (reprinted, same title as in 1899 a). https: // doi. org / 10.1080 / 00222939908678208","Richardson, H. (1905) A monograph on the isopods of North America. Bulletin of the United States National Museum, 54, I-Liii + 1 - 727. https: // doi. org / 10.5479 / si. 03629236.54. i","Gurjanova, E. F. (1936) Isopodes des Mers Orienalis. Fauna de L'URSS, Crustacees, 7 (3), i-XII + 1 - 279. [in Russian, Summary in German]","Schultz, G. A. (1969) How to know the marine isopod crustaceans. W. M. C. Brown Company Publishers, Dubuque, Iowa, 359 pp.","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]"]}

Astacilla frigida (Hansen, 1916) comb. nov. (Figs 34–35) Arcturus hystrix.— Ohlin, 1901: 30, fig. 6a–r (non G.O. Sars, 1877). Pleuroprion frigidum Hansen, 1916: 196–197, pl. XV, fig. 7a–b.— Boone, 1920: 30–31.— Kussakin, 1982: 427–428, fig. 317. Material examined: Syntypes, ZMUC-CRU-6464 (1 adult female), ZMUC-CRU-9401 (1 juvenile male), ZMUC- CRU-9402 (1 adult female, 1 juvenile male, 1 adult male), ZMUC-CRU-9403 (1 male, 1 Manca II stage, 4 females), all from 72°53´N, 20°36´W. Other material. ZMH-K-39770 (1 specimen, male, 8.5 mm length, ARK IX/2, station 179, Northeast Water Polynya, off Greenland). Diagnosis: Body of females with many long and narrow, bluntly pointed spines, spines forming neat row across each pereonite; five rows of spines across pereonite 4, additionally pair of spines between first and second row; pereonite 4 0.3 times body length, anteriorly paralell, narrowing posteriorly; 5.9 times longer than third pereonite; dorsally wider than pereonite 3. Pereonites 5 to 7 progressively shorter posteriorly; pleotelson oval, tapering towards rounded apex, with rows of spines across anterior and middle part of pleotelson, lateral margins with spines, distal end without spines. All pleonites fused into pleotelson; total length of pleotelson about combined lengths of pereonites 5 to 7. Eyes rounded, lateral. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna long, about 0.7 of total body length; robust, with few large spines on second segment; large spines distally on third segment. Pereopod 1 with long and strong unguis on dactylus, pereopods 2–4 without dactylus. Three spines present on each basis of pereopods 5 to 7. Pereopods 5–7 with two ungues, secondary robust. Oostegites present on pereopod 1–4. Male smaller than female. Pattern of spination as in females, spines smaller than in females and more robust; pereonite 4 narrow, dorsally about as wide (excluding spines) as pereonite 3. Penial plate laminar, with ridge on one side. Pleopod 1 with 5 coupling hooks on peduncle; exopod with proximal 2 plumose setae; 5 apical plumose setae respectively on endo- and exopode. Pleopod 2 endopod with 7, exopod with 11 (omitted in Fig. 35) apical plumose setae. Endopod slightly longer than exopod. Exopod fringed on outside with small fine setae. Appendix masculina without ridge, bifid, slightly longer than endopod. Uropod with exopod, inner ramus with 3 apical setose setae and one distal setose seta. Remarks: Hansen´s (1916) description of this species was rather short and sparsely illustrated. No description was provided of the pereopods and the pleopods. Examination of the type material reveals that this species does belongs in neither Pleuroprion nor Spectrarcturus. The species is here transferred for the time being to Astacilla, as diagnosed by King (2003). Astacilla needs revision (King 2003). Distribution: East Greenland, at depths between 90 and 320 m (Kussakin 1982; Brandt 1997)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 45-49, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Hansen, H. J. (1916) Crustacea Malacostraca III, Isopoda. The Danish Ingolf Expedition, 3 (5), 1 - 262.","Ohlin, A. (1901) Arctic Crustacea I. Leptostraca, Isopoda, Cumacea. Bihang till Kongliga Svenska Vetenskaps-Akademiens Handlingar, 26 (Part 4, No. 12), 1 - 54.","Sars, G. O. (1877) Prodromus descriptionis crustaceorum et pycnogonidarum, quae in expeditione norvegica anno 1876 observavit. Archiv for Mathematik og Naturvidenskab, 2, 237 - 271.","Boone, P. L. (1920) The Isopoda of the Canadian Arctic and adjoining regions. Report of the Canadian Arctic Expedition 1913 - 1918, 7 (D), 3 - 40.","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Kussakin, O. G. (1972) Isopoda from the coastal zone of the Kurile Islands. III. Three new arcturids from the Middle Kurils with taxonomic remarks on the family Arcturidae. Crustaceana, Supplement 3, 178 - 189.","King, R. A. (2003) First valid record of Astacilla Cordiner, 1793 in Australia, with description of a new species (Crustacea: Isopoda: Arcturidae). Records of the Western Australian Museum, 21, 359 - 366. https: // doi. org / 10.18195 / issn. 0312 - 3162.21 (4). 2003.359 - 366","Brandt, A. (1997) Biodiversity of peracarid crustaceans (Malacostraca) from the shelf down to the deep Arctic Ocean. Biodiversity and Conservation, 6, 1533 - 1556. https: // doi. org / 10.1023 / A: 1018318604032"]}

Spectrarcturus iturupicus (Kussakin & Mezhov, 1979) comb. nov. (Fig. 32) Pleuroprion iturupicum Kussakin & Mezhov, 1979: 145–148, figs 3–4. — Kussakin, 1982: 435–437, figs 323–324. Material examined: Paratype female, ZIN RAS cat. no. 3/49358, station 44, South Kurile Islands, Iturup Island. Diagnosis: Body with numerous small tubercles; mid-dorsally pair of somewhat longer, robust spines; pereonite 4 0.18 times body length; posteriorly narrow, twice as long as second and third together. Pleotelson short, with numerous small tubercles and pairs of short spines, posterior margin rounded, large lateral spine near ventral margin. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna short and robust, about 0.6 of total body length. Spines on basis of pereopods 5 to 7. Oostegites present on pereopod 5, as small lobes. Remarks: Detailed examination of the mouthparts, the pleopods and the uropods was not possible. Kussakin & Mezhov (1979) provided only illustrations of the lateral view of the habitus, first antenna, maxilliped and pereopods 1, 2 and 7. The same illustrations were provided by Kussakin (1982). From Kussakin & Mezhov (1979) and our observations it is clear that the species fits well into Spectrarcturus. The species can be distinguished from other species of Spectrarcturus on the body shape, the numerous small tubercles on the body and the shape of the pleotelson. The male is not known. Distribution: Kurile Islands, at depth between 125–146 m (Kussakin & Mezhov 1979)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on pages 42-45, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Kussakin, O. G. & Mezhov, B. V. (1979) Isopod Crustacea of the sublittoral and the upper bathyal zone of the Kurile Islands. In: Kussakin, O. G. (Ed.), Biology of the shelf of the Kurile Islands. Academy of Sciences, Far East Center, USSR, Moscow, pp. 125 - 199. [in Russian]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]"]}

Family Holidoteidae Wägele, 1989 Holidoteinae Wägele, 1989: 137. Holidoteidae—Poore 2001: 223.— Poore 2003: 1807–1809.— Kensley, Schotte & Poore, 2007: 440. Diagnosis (slightly modified from Poore 2003): Body straight, more or less flattened or semi-cylindrical. Head and pereonite 1 fused. Pereonite 4 of similar length to pereonite 3, not geniculate. All pleonites fused into pleotelson, or pleonite 1 articulating with fused pleotelson. Body smooth or slightly sculptured, or variously spinose or rugose; pleotelson without dorsolateral ridges ending in mediodorsal posterior spine. Dorsal coxal plates 2–7 obsolete, bases of pereopods exposed, or 2–7 obsolete and with expanded marginal tergites (females only). Mouthparts and pereopod 1 visible in lateral view (may be hidden by expanded tergites). Eyes well developed, or reduced or lost (rare). Antenna 2 flagellum of 2 or 3 articles plus distal claw. Pereopod 1 gnathopod, pereopods 2–4 elongated, differentiated from ambulatory pereopods 5–7. Pereopod 1 dactylus evenly curved along anterior margin, evenly tapering. Pereopods 2–4 with scattered and uneven long setae (sometimes pappose) along posterior margins; with short dactylus, unguis longer and setiform; pereopod 4 similar to pereopod 3. Pleonite 1 peduncle more elongate than on other pleopods; with marginal setae on rami longer than or equal to length of rami. Uropodal exopod shorter than wide, bearing single prominent robust seta, endopod with robust apical seta. Pereopods of males without dense fur of fine setae. Penes fused as single penial plate; penial plate apically bifid and splayed. Pleopod 1 exopod thichened and with groove on posterior face, with overlapping rows of simple and plumose setae along lateral margin, terminating at subdistal excavation; with groove on posterior face of exopod ending on distolateral lobed tip, separated from most of lateral margin by notch. Pleopod 2 with appendix masculina about as long as endopod, basally less than half width of endopod. Oostegites 1–4 functional, supported by coxal lobes; oostegite 5 absent. Remarks: Holidoteidae contains three genera, Neoarcturus Barnard, 1914a, Austroarcturus Kensley, 1975 and the monotypic Holidotea Barnard, 1920 (Poore 2003). The arrangement of pereopods 2–4 and the form of the male pleopod 1 differentiate these genera. Pleuroprion is now added., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 3, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Wagele, J. W. (1989) Evolution und phylogenetisches System der Isopoda. Stand der Forschung und neue Erkenntnisse. Zoologica, Stuttgart, 140, 1 - 262.","Poore, G. C. B. (2003) Revision of Holidoteidae, an endemic southern African family of Crustacea, and re-appraisal of taxa previously included in its three genera (Isopoda: Valvifera). Journal of Natural History, 37, 1805 - 1846. https: // doi. org / 10.1080 / 00222930210133273","Kensley, B., Schotte, M. & Poore, G. C. B. (2007) New species and records of valviferan isopods (Crustacea: Isopoda: Valvifera) from the Indian Ocean. Proceedings of the Biological Society of Washington, 120, 429 - 445. https: // doi. org / 10.2988 / 0006 - 324 X (2007) 120 [429: NSAROV] 2.0. CO; 2","Barnard, K. H. (1914 a) Contributions to the crustacean fauna of South Africa. 1. Additions to the marine Isopoda. Annals of the South African Museum, 10, 197 - 230. https: // doi. org / 10.5962 / bhl. part. 9314","Kensley, B. (1975) Marine Isopoda from the continental shelf of South Africa. Annals of the South African Museum, 67 (4), 35 - 89.","Barnard, K. H. (1920) Contributions to the crustacean fauna of South Africa. 6. Further additions to the list of marine Isopoda. Annals of the South African Museum, 17 (5), 319 - 438, pls. XV-XVII. https: // doi. org / 10.5962 / bhl. part. 22318"]}

Family Arcturidae Dana, 1849 Arcturidae Dana, 1849: 359, 360.— Kensley, 1978: 16, 17 (part).— Kensley & Schotte, 1989: 252 (part).— Kussakin, 1982: 270–272 (part).— Poore, 2001: 222–223. Arcturinae.— Wägele, 1989: 138.— Wägele, 1991: 88 (part)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 14, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Dana, J. D. (1849) Conspectus Crustaceorum quae in orbis terrarium circumnavigatione, Carolo Wilkes e classe Republicae Foederate Duce, Isopoda I. American Journal of Science and Arts, Series 2, 8, 424 - 427. https: // doi. org / 10.2307 / 20021076","Kensley, B. (1978) Guide to the marine isopods of Southern Africa. Trustees of the South African Museum, Cape Town, 173 pp.","Kensley, B. & Schotte, M. (1989). Guide to the marine isopod crustaceans of the Caribbean. Smithsonian Institution Press, Washington, D. C. and London, 308 pp. https: // doi. org / 10.5962 / bhl. title. 10375","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Poore, G. C. B. (2001) Isopoda Valvifera: Diagnoses and relationships of the families. Journal of Crustacean Biology, 21, 205 - 230. https: // doi. org / 10.1163 / 20021975 - 99990118","Wagele, J. W. (1989) Evolution und phylogenetisches System der Isopoda. Stand der Forschung und neue Erkenntnisse. Zoologica, Stuttgart, 140, 1 - 262.","Wagele, J. W. (1991) Antarctic Isopoda Valvifera. In: Wagele, J. W. & Sieg, J. (Eds.), Synopses of the Antarctic Benthos. Vol. 2. Koeltz Scientific Books, Koenigstein, pp. 1 - 213."]}

Spectrarcturus chlebovitschi (Kussakin, 1972) comb. nov. (Fig. 26) Pleuroprion chlebovitschi Kussakin, 1972: 183–186, figs 3–4. — Kussakin & Mezhov, 1979: 148.— Kussakin, 1982: 437–440, figs 325–326. Material examined: Paratype female, ZIN RAS number N 4/59458, R / V “PT-2”, station 56, 26 May 1955, Sea of Okhotsk, Aniva Bay. Diagnosis: Body with numerous large and small pointed tubercles, sometimes strongly bulbous at apex, forming row across each pereonite; three rows on pereonite 4. Pereonite 4 0.2 times body length; subparalell, 2 times longer than third pereonite. Pleotelson short, wide, bluntly truncated, slightly convex apically; anteriorly two pairs of middorsal spines, posteriorly with dense low tubercles; lateral margins extended to rounded projections, one mid-laterally and one near apex. Antennula short, reaching to distal end of second peduncular segment of antenna; first article dorsally with large spine. Antenna robust and intermediate in length, about 0.7 of total body length; pronounced rounded spines laterodorsally on second segment, two rounded spines on third segment. Spines on basis of pereopods 5 to 7. Remarks: The female was thoroughly described and illustrated by Kussakin (1972, 1982), but he did not illustrate the male. He stated that the male is smaller and more slender, and not expanded in the middle pereonites (Kussakin 1972). There is considerable variation in the form of the spines on the body, these being either thick, robust and blunt, or rounded, with bulbous tip (see Kussakin 1972: fig. 3). These extremes can even occur on the same specimens (Kussakin 1972). The species can be distinguished from all other Spectrarcturus species on the shape of the dorsal spines/tubercles and on the robust antenna. Distribution: Kurile Islands, at depths between 6 and 65 m (Kussakin 1982).

Spectrarcturus fabulosus (Gurjanova, 1955) comb. nov. (Fig. 27) Pleuroprion fabulosus Gurjanova, 1955: 225–228, figs 13–14. Pleuroprion fabulosum.— Kussakin & Mezhov, 1979: 149.— Kussakin, 1982: 440–444, figs 327–329.— Kussakin & Vasina, 1990: 50–51, figs 3–4. Material examined: Paratype female, ZIN RAS cat. no. 3/22841, Kobjakova R / V “Toporok“, station 101, 14 September 1949, South Kurile Islands. Diagnosis: Body densely setose, with many slender, pointed spines, pair on each pereonite near midline of body, two pairs on pereonite 4; dorsolaterally single large spine and laterally additional spine on anterior pereonites; pereonite 4 0.2 times body length; trapezoid, 2 times longer than third pereonite. Pleotelson long, with few long spines anteriorly, lateral margins with spines, posterior part of pleotelson tapering towards apex. Antennula somewhat long, reaching about one third of length of third peduncular segment of antenna. Antenna long, slender, about 0.9 of total body length; pronounced spine mid-dorsally on second segment, spine distolaterally on fourth segment. Spines present on basis of pereopods 5–7. Oostegites present on pereopods 1–5, very small oostegite lobe on pereopod 5. Remarks: This species can be distinguished from the other species of Spectrarcturus on the dense setae of the body (also known in S. furcatus), the relatively long antennula and the narrowly pointed pleotelson, having only dorsal spines on the anterior most part of the pleotelson. The male is unknown. Distribution: Sea of Okhotsk, 385–414 m (Kussakin 1982; Kussakin & Vasina 1990)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 37, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Gurjanova, E. F. (1955) The isopod crustacean fauna (Isopoda) of the Pacific Ocean VI. New species of Valvifera from the Kurile-Sakhalin Region. Trudy Instituta Zoologii Akademia Nauk USSR, 21, 208 - 230. [in Russian]","Kussakin, O. G. & Mezhov, B. V. (1979) Isopod Crustacea of the sublittoral and the upper bathyal zone of the Kurile Islands. In: Kussakin, O. G. (Ed.), Biology of the shelf of the Kurile Islands. Academy of Sciences, Far East Center, USSR, Moscow, pp. 125 - 199. [in Russian]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]","Kussakin, O. G. & Vasina, G. S. (1990) Isopod crustaceans of the suborders Flabellifera and Valvifera from the bathyal region of the Kurile Islands. Systematics and Chorology of Marine Organisms. FEB RAS, Vladivostok, pp. 43 - 63. [in Russian]"]}

Astacilla frigida (Hansen, 1916) comb. nov. (Figs 34–35) Arcturus hystrix.— Ohlin, 1901: 30, fig. 6a–r (non G.O. Sars, 1877). Pleuroprion frigidum Hansen, 1916: 196–197, pl. XV, fig. 7a–b.— Boone, 1920: 30–31.— Kussakin, 1982: 427–428, fig. 317. Material examined: Syntypes, ZMUC-CRU-6464 (1 adult female), ZMUC-CRU-9401 (1 juvenile male), ZMUC- CRU-9402 (1 adult female, 1 juvenile male, 1 adult male), ZMUC-CRU-9403 (1 male, 1 Manca II stage, 4 females), all from 72°53´N, 20°36´W. Other material. ZMH-K-39770 (1 specimen, male, 8.5 mm length, ARK IX/2, station 179, Northeast Water Polynya, off Greenland). Diagnosis: Body of females with many long and narrow, bluntly pointed spines, spines forming neat row across each pereonite; five rows of spines across pereonite 4, additionally pair of spines between first and second row; pereonite 4 0.3 times body length, anteriorly paralell, narrowing posteriorly; 5.9 times longer than third pereonite; dorsally wider than pereonite 3. Pereonites 5 to 7 progressively shorter posteriorly; pleotelson oval, tapering towards rounded apex, with rows of spines across anterior and middle part of pleotelson, lateral margins with spines, distal end without spines. All pleonites fused into pleotelson; total length of pleotelson about combined lengths of pereonites 5 to 7. Eyes rounded, lateral. Antennula short, reaching little beyond distal end of second peduncular segment of antenna. Antenna long, about 0.7 of total body length; robust, with few large spines on second segment; large spines distally on third segment. Pereopod 1 with long and strong unguis on dactylus, pereopods 2–4 without dactylus. Three spines present on each basis of pereopods 5 to 7. Pereopods 5–7 with two ungues, secondary robust. Oostegites present on pereopod 1–4. Male smaller than female. Pattern of spination as in females, spines smaller than in females and more robust; pereonite 4 narrow, dorsally about as wide (excluding spines) as pereonite 3. Penial plate laminar, with ridge on one side. Pleopod 1 with 5 coupling hooks on peduncle; exopod with proximal 2 plumose setae; 5 apical plumose setae respectively on endo- and exopode. Pleopod 2 endopod with 7, exopod with 11 (omitted in Fig. 35) apical plumose setae. Endopod slightly longer than exopod. Exopod fringed on outside with small fine setae. Appendix masculina without ridge, bifid, slightly longer than endopod. Uropod with exopod, inner ramus with 3 apical setose setae and one distal setose seta. Remarks: Hansen´s (1916) description of this species was rather short and sparsely illustrated. No description was provided of the pereopods and the pleopods. Examination of the type material reveals that this species does belongs in neither Pleuroprion nor Spectrarcturus. The species is here transferred for the time being to Astacilla, as diagnosed by King (2003). Astacilla needs revision (King 2003). Distribution: East Greenland, at depths between 90 and 320 m (Kussakin 1982; Brandt 1997).

Spectrarcturus chlebovitschi (Kussakin, 1972) comb. nov. (Fig. 26) Pleuroprion chlebovitschi Kussakin, 1972: 183–186, figs 3–4. — Kussakin & Mezhov, 1979: 148.— Kussakin, 1982: 437–440, figs 325–326. Material examined: Paratype female, ZIN RAS number N 4/59458, R / V “PT-2”, station 56, 26 May 1955, Sea of Okhotsk, Aniva Bay. Diagnosis: Body with numerous large and small pointed tubercles, sometimes strongly bulbous at apex, forming row across each pereonite; three rows on pereonite 4. Pereonite 4 0.2 times body length; subparalell, 2 times longer than third pereonite. Pleotelson short, wide, bluntly truncated, slightly convex apically; anteriorly two pairs of middorsal spines, posteriorly with dense low tubercles; lateral margins extended to rounded projections, one mid-laterally and one near apex. Antennula short, reaching to distal end of second peduncular segment of antenna; first article dorsally with large spine. Antenna robust and intermediate in length, about 0.7 of total body length; pronounced rounded spines laterodorsally on second segment, two rounded spines on third segment. Spines on basis of pereopods 5 to 7. Remarks: The female was thoroughly described and illustrated by Kussakin (1972, 1982), but he did not illustrate the male. He stated that the male is smaller and more slender, and not expanded in the middle pereonites (Kussakin 1972). There is considerable variation in the form of the spines on the body, these being either thick, robust and blunt, or rounded, with bulbous tip (see Kussakin 1972: fig. 3). These extremes can even occur on the same specimens (Kussakin 1972). The species can be distinguished from all other Spectrarcturus species on the shape of the dorsal spines/tubercles and on the robust antenna. Distribution: Kurile Islands, at depths between 6 and 65 m (Kussakin 1982)., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 35, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Kussakin, O. G. (1972) Isopoda from the coastal zone of the Kurile Islands. III. Three new arcturids from the Middle Kurils with taxonomic remarks on the family Arcturidae. Crustaceana, Supplement 3, 178 - 189.","Kussakin, O. G. & Mezhov, B. V. (1979) Isopod Crustacea of the sublittoral and the upper bathyal zone of the Kurile Islands. In: Kussakin, O. G. (Ed.), Biology of the shelf of the Kurile Islands. Academy of Sciences, Far East Center, USSR, Moscow, pp. 125 - 199. [in Russian]","Kussakin, O. G. (1982) Morskye I solonovatovodnye ravnonogie rakoobrasnye (Isopoda) cholodnix I umerennix vod severnogo polushariya [Marine and brackish water like-footed crustaceans (Isopoda) of cold and temperate waters of the North- ern Hemisphere]. Podotryadi Anthuridea, Microcerberidea, Valvifera, Tyloidea. Opredeliteli po Faune SSSR, Izdavaemye Zoologicheskim Institutom Akademii Nauk SSSR, 131 (2), 1 - 463. [in Russian]"]}

Genus Astacilla Cordiner, 1793 Astacilla Cordiner, 1793.— King, 2003: 359–361.— Kensley, Schotte and Poore, 2007: 436–437. Diagnosis (from King 2003): Body strongly geniculate between pereonites 4 and 5, cylindrical, with no dorsal ridge. Antenna slender or robust, with 2 or 3 flagellar articles, flagellum distally with claw. Maxillipedal palp with all segments free, palp article 3 similar width as article 2. Pereonite 4 elongate; pereonite 4 of male and female of similar length. Pereopod 1 setose, with unguis (rarely without). Pereopods 2–4 present and functional as setose appendages, dactylus absent. Pereopods 2–4 cylindrical, held close to mouthparts, able to extend past mouthparts, setae in rows, setae as long as segment, flexion between carpus and propodus present. Pereopods 5–7 with 2 ungues, secondary unguis robust. Female functional brood pouch majority made up of pereonite 4 (or 3 and 4). Oostegite 5 absent. Male penial plate narrow, apex simple. Male pleopod 1 with lateral notch, with 3 lateral setae, lateral setae of similar length. Male pleopod 2 with appendix masculina tapered, without ridge, distally not widened, straight, elongated. Uropodal exopod present, 3 setae on inner ramus., Published as part of Stransky, Bente, Svavarsson, Jörundur, Poore, Gary C. B. & Kihara, Terue Cristina, 2020, Revision of Pleuroprion zur Strassen, 1903 (Holidoteidae) and re-evaluation of Spectrarcturus Schultz, 1981 (Arcturidae) (Crustacea, Isopoda, Valvifera), pp. 1-52 in Zootaxa 4894 (1) on page 45, DOI: 10.11646/zootaxa.4894.1.1, http://zenodo.org/record/4315364, {"references":["Cordiner, C. (1793) Remarkable ruins, and romantic prospects, of North Britain. With ancient monuments, and singular subjects of natural history. Peter Mazell, London, 96 pls. with letterpress.","King, R. A. (2003) First valid record of Astacilla Cordiner, 1793 in Australia, with description of a new species (Crustacea: Isopoda: Arcturidae). Records of the Western Australian Museum, 21, 359 - 366. https: // doi. org / 10.18195 / issn. 0312 - 3162.21 (4). 2003.359 - 366","Kensley, B., Schotte, M. & Poore, G. C. B. (2007) New species and records of valviferan isopods (Crustacea: Isopoda: Valvifera) from the Indian Ocean. Proceedings of the Biological Society of Washington, 120, 429 - 445. https: // doi. org / 10.2988 / 0006 - 324 X (2007) 120 [429: NSAROV] 2.0. CO; 2"]}

Genus Scallasis Bate, 1888 Scallasis Bate, 1888: 34.��� Manning & Felder 1991: 780.��� Poore et al. 2019: 99. Callianassa (Scallasis).��� Borradaile 1903: 547���548 (partim). Cheramus. ��� Sakai 2011a: 363���365 (partim). Remarks. The genus was rediagnosed by Poore et al. (2019: 99) after thorough molecular and morphological analysis (Robles et al. 2020). The genus is recognised by the combination of a narrow rostrum, eyestalks with acute apices, a narrow maxilliped 3 ischium-merus, a simple or bifid spine on the merus of the major cheliped, and strong spiniform setae on the face of the uropodal endopod and on the face of the telson. As noted above, Poore et al. (2019: tab. 1, 2) included seven species, all from the Indo-West Pacific: S. amboinae, S. andamaniensis, S. caledonica, S. contipes, S. pygmaea, S. spinophthalma and S. tonkinae. Some, however, have been synonymised with others and later removed from synonymy (see S. amboinae, S. caledonica and S. tonkinae below). In his major axiidean review, Sakai (2011a) regarded the four specific taxa, Scallasis amboinae, Callianassa caledonica, Callianassa (Cheramus) pygmaea and Callianassa (Scallasis) tonkinae as valid species of Trypaea Dana, 1852. Characterisation of these species is limited without reference to type material ��� we have relied for most on published works but believe many descriptions and figures omit critical characters not usually noted in callianassid descriptions in the past and which have been often overlooked. For example, the facial spiniform setae on the uropodal rami were unexpected or considered unimportant by earlier authors and are difficult to observe without appropriate lighting or staining. The scaphocerite is acute and short in species we have observed but not mentioned in most descriptions. There appear few reliable differences between species in the rostrum (triangular, sharp, reaching the cornea) and eyestalks (tapering to acute anterior lobes) but we see species differences in maxilliped 3 and in the chelipeds. Adding to the difficulty differentiating species is the paucity of individuals, and differences between sexes, growth stages and individuals. Nevertheless, we have prepared short diagnoses of the seven species of Scallasis recognised here. Scallasis caledonica, S. inermis n. sp. and S. spinophthalma are known from both sexes. Pleopod 1 is present in males of all three but variously developed, possibly due to the maturity of the specimens examined. Pleopod 2 is present in two species, not in S. caledonica. Chelipeds are apparently sexually dimorphic only in S. inermis n. sp. but this species may be the only one where a fully adult male is known., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on page 402, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Bate, S. C. (1888) Report on the Crustacea Macrura collected by H. M. S. Challenger during the years 1873 - 76. Report on the Scientific Results of the Voyage of H. M. S. \" Challenger \" during the Years 1873 - 76, Zoology, 24 (i-xc), 1 - 942, pls. 1 - 157.","Manning, R. B. & Felder, D. L. (1991) Revision of the American Callianassidae (Crustacea, Decapoda, Thalassinidea). Proceedings of the Biological Society of Washington, 104, 764 - 792.","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","Borradaile, L. A. (1903) On the classification of the Thalassinidea. Annals and Magazine of Natural History, Series 7, 12, 534 - 551 + 638 (addendum) https: // doi. org / 10.1080 / 00222930309487049","Sakai, K. (2011 a) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Robles, R., Dworschak, P. C., Felder, D. L., Poore, G. C. B. & Mantelatto, F. L. (2020) A molecular phylogeny of Callianassidae and related families (Crustacea: Decapoda: Axiidea) with morphological support. Invertebrate Systematics, 34. https: // doi. org / 10.1071 / IS 19021","Dana, J. D. (1852) Macroura. Conspectus Crustaceorum &. Conspectus of the Crustacea of the Exploring Expedition under Capt C. Wilkes, U. S. N. Proceedings of the Academy of Natural Sciences of Philadelphia, 6, 10 - 28."]}

Scallasis caledonica (Ngoc-Ho, 1991) Callianassa caledonica Ngoc-Ho, 1991: 285���287, fig. 2.��� Dworschak 2007: 307. Trypaea caledonica.��� Sakai 2011a: 395. Scallasis caledonica.��� Poore et al. 2019: 143. Type material. Holotype: New Caledonia, Lagon Est, 21 m, 13 January 1987, female (cl 5.0 mm), MNHN-Th 1072. Paratype: Same data as holotype, 1 female lacking pleon (cl 5.0 mm), MNHN-Th 1073; 1 male lacking pleon (cl 4.0 mm), 2 males (cl 4.5, 5.0 mm), MNHN-Th 1074. Diagnosis. Pleomere 6 as long as wide. Telson 0.8 times as long as wide; greatest width 1.2 times posterior width. Maxilliped 3 ischium-merus 3 times as long as wide; merus free distal margin transverse, rounded. Female major cheliped ischium lower margin with 6���8 small spines; merus lower margin with simple proximal spine; palm 0.9 times as long as carpus. Male major cheliped merus lower margin as in female; dactylus as in female. Minor cheliped ischium lower margin with 10 small serrations; merus lower margin with 1 oblique spine at midpoint. Male pleopod 1 of 1 minute article. Male pleopod 2 absent. Uropodal endopod anterior margin with small spine about two-thirds along; dorsal surface with 1 long proximal spiniform seta, usually plus 1 shorter submarginal seta; exopod anterior margin with small spiniform seta about three-quarters along. Distribution. Known only from the type locality in New Caledonia. Remarks. Scallasis caledonica was originally described on the basis of five specimens from Lagon Est, New Caledonia (Ngoc-Ho 1991; as Callianassa). We have re-examined the type material and can confirm the accuracy of Ngoc-Ho���s figures, the only exception being the presence of two long facial spiniform setae and another distally on the anterior margin of the uropodal endopod. The male possesses a minute, pear-shaped pleopod 1 but lacks pleopod 2. Ngoc-Ho (1991) noted that the chelipeds were only slightly sexually dimorphic. Differences from S. amboinae are subtle: the distal margin of the merus of maxilliped 3 is less oblique, and the major cheliped is more compact, its meral tooth being proximal and triangular, rather than spine-like. Sakai (1999) considered Callianassa caledonica a junior synonym of ��� Callianassa ��� pygmaea while Dworschak (2007) considered it a valid species. Sakai���s (2010) treatment of Callianassa caledonica was not consistent: under the account of Trypaea andamaniensis, he stated ��� T. caledonica is considered to be a separate species���, whereas under the account of Trypaea tonkinae he viewed it as a questionable synonym., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on page 408, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Ngoc-Ho, N. (1991) Sur quelques Callianassidae et Upogebiidae de Nouvelle Caledonie (Crustacea, Thalassinidea). In: Richer de Forges, B. (Ed.), Le benthos des fonds meubles des lagons de Nouvelle Caledonie. Vol. 1. ORSTOM Editions, Paris, pp. 281 - 311.","Dworschak, P. C. (2007) Thalassinideans shrimps of New Caledonia. In: Payri, C. E. & Richer de Forges, B. (Eds.), Documents Scientifiques et Techniques. II 7. Compendium of Marine Species of New Caledonia. 2 eme Edition. IRD, Noumea, pp. 305 - 307.","Sakai, K. (2011 a) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","Sakai, K. (1999) Synopsis of the family Callianassidae, with keys to subfamilies, genera and species, and the description of new taxa (Crustacea: Decapoda: Thalassinidea). Zoologische Verhandelingen, 326, 1 - 152.","Sakai, K. (2010) Callianassoidea from the Gulf of Tonkin and the Red sea, in the Zoological Museum of Moscow University (Decapoda, Thalassinidea). Crustaceana, 83, 1431 - 1467. https: // doi. org / 10.1163 / 001121610 X 538174"]}

Scallasis tonkinae (Grebenyuk, 1975) Callianassa (Scallasis) tonkinae Grebenjuk, 1975: 302 ���303, fig. 3. Callianassa tonkinae.��� Sakai 1999: 52.��� Sakai 2005: 118. Trypaea tonkinae.��� Sakai 2011a: 411.���? Sakai 2011b: 1119. Scallasis tonkinae.��� Poore et al. 2019: 143. Not Callianassa tonkinae��� Sakai 2002: 503���506, figs 24, 25 = S. andamaniensis (Sakai, 2010). Type locality. Gulf of Tonkin. Diagnosis. Pleomere 6 1.3 times as long as wide. Telson 0.7 times as long as wide; greatest width 1.3 times posterior width. Maxilliped 3 ischium-merus 3.2 times as long as wide; merus free distal margin transverse, rounded. Female major cheliped ischium lower margin with 4 small spines; merus lower margin with bifid proximal spine; palm 1.2 times as long as carpus. Distribution. Known with certainty only from the type locality. Remarks. Placement of Callianassa (Scallasis) tonkinae in Scallasis relies on Grebenjuk���s (1975) figures of the maxilliped 3, pereopod 3 and telson, and to a lesser extent the major cheliped and uropod. The proximal bifid meral spine on the female major cheliped is similar to that seen in male S. caledonica and S. inermis n. sp. The structure of the eyestalk appears unique in Scallasis in the terminal location of the cornea and the lack of a distomesial projection. No dorsal plate, facial spiniform setae or margin tooth were figured on the uropod ��� we assume they were overlooked. Dworschak (2007) suggested that Callianassa tonkinae was a junior synonym of Callianassa amboinae. Sakai (2010) referred the material identified as Callianassa tonkinae from the Andaman Sea by Sakai (2002) to a new taxon Trypaea andamaniensis. Sakai (2011b) identified specimens from the Red Sea, 53 m, and Vietnam, 46 m as ��� Trypaea ��� tonkinae. The Red Sea is far west of other records of this genus but we were unable to examine this material. Grebenyuk���s types are apparently lost; they were not found in the Zoological Museum of the Moscow State University where Grebenyuk worked (I. Marin, pers. comm. 26 Jan 2020)., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on page 419, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Grebenyuk, L. P. (1975) Dva novykh vida desyatinogikh rakoobraznykh nadsemeistva Thalassinidea [Two new decapod species of the superfamily Thalassinidea]. Zoologischeskii Zhurnal, 54, 299 - 304.","Sakai, K. (1999) Synopsis of the family Callianassidae, with keys to subfamilies, genera and species, and the description of new taxa (Crustacea: Decapoda: Thalassinidea). Zoologische Verhandelingen, 326, 1 - 152.","Sakai, K. (2005) Callianassoidea of the world (Decapoda, Thalassinidea). Crustaceana Monographs, 4, 1 - 285.","Sakai, K. (2011 a) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Sakai, K. (2011 b) Callianassidae (II) and Upogebiidae from the Gulf of Tonkin and the Red Sea, in the Zoological Museum of Moscow University (Decapoda, Thalassinidea). Crustaceana, 84, 1117 - 1137. https: // doi. org / 10.1163 / 001121611 X 586684","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","Sakai, K. (2002) Callianassidae (Decapoda, Thalassinidea) in the Andaman Sea, Thailand. Phuket Marine Biological Center Special Publication, 23, 461 - 532.","Sakai, K. (2010) Callianassoidea from the Gulf of Tonkin and the Red sea, in the Zoological Museum of Moscow University (Decapoda, Thalassinidea). Crustaceana, 83, 1431 - 1467. https: // doi. org / 10.1163 / 001121610 X 538174","Dworschak, P. C. (2007) Thalassinideans shrimps of New Caledonia. In: Payri, C. E. & Richer de Forges, B. (Eds.), Documents Scientifiques et Techniques. II 7. Compendium of Marine Species of New Caledonia. 2 eme Edition. IRD, Noumea, pp. 305 - 307."]}

A poorly known callianassid ghost shrimp species, Scallasis amboinae Bate, 1888, is redescribed and illustrated on the basis of the holotype and new material from Papua New Guinea. A new species, S. inermis, is described from the Ryukyu Islands, Japan. Callianassa (Cheramus) pygmaea De Man 1928 is synonymised with S. amboinae. All seven species of Scallasis are diagnosed and compared.

Scallasis andamaniensis (Sakai, 2010) Callianassa tonkinae.��� Sakai 2002: 503���506, figs 24, 25. Trypaea andamaniensis Sakai, 2010: 1438. Scallasis andamaniensis.��� Poore et al. 2019: 143. Type locality. Andaman Sea, 09��00���N 97��53���E, 65��� 70 m. Diagnosis. Pleomere 6 1.2 times as long as wide. Telson 1 times as long as wide; greatest width 1.2 times posterior width. Maxilliped 3 ischium-merus 3 times as long as wide; merus free distal margin oblique. Female major cheliped ischium lower margin with 4 strong spines; merus lower margin with simple proximal spine; palm 1 times as long as carpus. Uropodal endopod anterior margin with small spine about two-thirds along. Distribution. Known only from the type locality in the Andaman Sea. Remarks. Sakai (2010) reidentified as Trypaea andamaniensis specimens from the Andaman Sea first identified by him as Callianassa tonkinae. The uropod, telson and maxilliped 3 appear identical to those of S. amboinae but the female cheliped is more robust and with a stronger more proximal meral spine. A juvenile male was reported without pleopod 1 and with a bi-articulate pleopod 2 (cf. S. caledonica, S. inermis n. sp. below)., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on page 407, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Sakai, K. (2010) Callianassoidea from the Gulf of Tonkin and the Red sea, in the Zoological Museum of Moscow University (Decapoda, Thalassinidea). Crustaceana, 83, 1431 - 1467. https: // doi. org / 10.1163 / 001121610 X 538174","Sakai, K. (2002) Callianassidae (Decapoda, Thalassinidea) in the Andaman Sea, Thailand. Phuket Marine Biological Center Special Publication, 23, 461 - 532.","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05"]}

Scallasis spinophthalma (Sakai, 1970) (Fig. 10) Callianassa (Cheramus) spinophthalma Sakai, 1970: 40���45, figs 2, 3, 4a, b. Callianassa spinophthalma. ��� Sakai 1999: 52.��� Sakai 2005: 103. Cheramus spinophthalmus.��� Komai et al. 2002: 39, fig. 7.��� Sakai 2011a: 372. Scallasis spinophthalma.��� Poore et al. 2019: 143. Material examined. TRV Toyoshio-maru 2001-11 cruise, stn 10, Sea of Japan off Hagi, Yamaguchi Prefecture, 34��40.00���N 131��10.00���E, 99 m, 5 July 2001, dredge, 1 male (cl 3.3 mm), 1 female (cl 2.8 mm), 5 ovigerous females (cl 3.3���3.6 mm), CBM-ZC 6166; stn 12, off Kawajiri-misaki, Yamaguchi Prefecture, 34��28.40���N 130��52.10���E, 84 m, 7 July 2001, dredge, 1 female (cl 2.8 mm), 4 ovigerous females (cl 2.3���3.5 mm), CBM-ZC 6170. Type locality. Off Tsushima Islands (34��58'N 129��26.9'E), southern part of the Sea of Japan, at depth of 210 m. Diagnosis. Pleomere 6 as long as wide. Telson 0.8 times as long as wide; greatest width 1.4 times posterior width. Maxilliped 3 ischium-merus 2.2 times as long as wide; merus free distal margin rounded, slightly produced. Major cheliped strongly sexually dimorphic. Female major cheliped ischium lower margin with 5���7 strong spines; merus lower margin with conspicuous spine at midpoint, followed by few smaller spines proximally; palm subequal in length to carpus. Male major cheliped merus lower margin with trifid spines proximally; palm 1.6 as long as carpus; dactylus with smooth occlusal margin. Minor cheliped ischium lower margin with serration of 5���8 spines; merus lower margin with 1 oblique spine at midpoint. Male pleopod 1 of 2 small articles. Male pleopod 2 biramous. Uropodal endopod anterior margin with minute spine at posterior two-thirds; upper surface with 2 long spiniform setae on midline and 1 submarginal minute spiniform seta proximal to midlength; exopod anterior margin unarmed, upper surface with 1 long submarginal spiniform seta at midpoint. Distribution. Southern part of the Sea of Japan; at depths of 99��� 210 m. Remarks. Scallasis spinophthalma was originally described on the basis of six female specimens (including three ovigerous specimens) and four detached chelipeds. An ovigerous specimen (cl 4.3 mm) was designated as holotype. The species is notable for the broad maxilliped 3 ischium-merus and the distal margin of the merus much more rounded than in any other congeneric species (Sakai 1970, fig. 4a; Komai et al. 2002: fig. 9F, G). The species possesses a bi-articulate male pleopod 1 and biramous pleopod 2, more developed than in other species. Komai et al. (2002) did not illustrate female chelipeds, here illustrated (Fig. 10B, C); the telson and left uropod are re-illustrated (Fig. 10A, D) to show armature (facial spiniform setae and a spine on the uropodal endopod anterior margin) which were overlooked., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on pages 417-419, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Sakai, K. (1970) A small collection of the thalassinideans from the waters around Tsushima Islands, Japan, including a new species of Callianassa (Crustacea, Anomura). Publications of the Seto Marine Biological Laboratory, 28 (1), 37 - 47. https: // doi. org / 10.5134 / 175621","Sakai, K. (1999) Synopsis of the family Callianassidae, with keys to subfamilies, genera and species, and the description of new taxa (Crustacea: Decapoda: Thalassinidea). Zoologische Verhandelingen, 326, 1 - 152.","Sakai, K. (2005) Callianassoidea of the world (Decapoda, Thalassinidea). Crustaceana Monographs, 4, 1 - 285.","Komai, T., Ohtsuka, S., Nakaguchi, K. & Go, A. (2002) Decapod crustaceans collected from the southern part of the Sea of Japan in 2000 - 2001 using TRV Toyoshio-maru. Natural History Research, 7 (1), 19 - 73.","Sakai, K. (2011 a) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05"]}

Scallasis inermis n. sp. [New Japanese name: Mame-sunamoguri] (Figs 4���9) http://zoobank.org/ urn:lsid:zoobank.org:act: 68C54DF6-7729-4E82-8785-87AAD5CC1A14 Type material. Holotype: Japan, Okinawa Island, Ohura Bay, Umi-saboten diving point (stn D1), 3���20 m, 18 June 2009, SCUBA diving, yabby pump, male (cl 3.7 mm; photographed), coll. Y. Fujita and T. Naruse, CBM-ZC 14140. Paratypes: Japan, Okinawa Island, Ohura B ay, Tettou-oki diving point, 23 m, muddy sand, 9 November 2013, SCUBA diving, yabby pump, coll. Y. Fujita, 1 male (cl 3.7 mm; photographed), RUMF-ZC-04571; same data, 3 males (cl 3.6, 3.6, 3.7 mm), 1 ovigerous female (cl 3.6 mm), CBM-ZC 14141���14144. Diagnosis. Pleomere 6 1.1 times as long as wide. Telson 1 times as long as wide; greatest width 1.5 times posterior width. Maxilliped 3 ischium-merus 2.6 times as long as wide; merus free distal margin oblique. Female major cheliped ischium lower margin with 1���5 small spines; merus lower margin unarmed; palm 0.7 times as long as carpus. Male major cheliped merus lower margin with bifid proximal spine; palm 1.4���1.6 as long as carpus; dactylus with 2 notches on cutting margin. Minor cheliped ischium lower margin with 2 or 3 small spines; merus lower margin unarmed. Male pleopod 1 of 1 minute article, or of 2 small articles. Male pleopod 2 biramous. Uropodal endopod anterior margin with small spine about two-thirds along; dorsal surface with 1���3 minute proximal spiniform setae; exopod anterior margin with small spiniform seta about three-quarters along. Description. Rostrum narrowly triangular, spiniform, directed forward, with slight ventral carina, falling slightly short of distal ends of eyestalks. Carapace subequal in length to pleomeres 1 and 2 combined; orbital margins concave; anterolateral projections triangular with subacute tip; excavation inferior to anterolateral projections deep, U-shaped; deep cervical groove across 0.8 length of carapace, without postrostral transverse groove; linea thalassinica distinct, extending to posterolateral margin of carapace. Thoracic sternite 7 subpentagonal with slightly projecting anteromedian margin; ventral surface with shallow median groove. Pleomere 1 narrowing anteriorly in dorsal view; pleuron with poorly defined ventral margin. Pleomere 2 pleuron posterolateral margin slightly expanded, without tuft of setae. Pleomeres 3���5 pleura each with patch of plumose setae; posterolateral margins slightly expanded; pleuron 3 with tuft of long setae adjacent to posterolateral margin, pleura 4 and 5 with tuft or longitudinal row of setae on posterior parts, respectively. Pleomere 6 about 1.1 times as long as wide, subquadrate, slightly narrowing posteriorly, lacking ventrolateral projection; lateral margin with shallow notch at about posterior 0.2. Telson trapezoidal, narrowing posteriorly, approximately as long as wide, broadest at anterior 0.2; greatest width 1.5 times posterior width; dorsal surface medially with some spiniform setae in short transverse row anterior to midlength; lateral margin unarmed; 2 pairs of small spiniform setae at rounded posterolateral angles; posterior margin shallowly concave medially, unarmed or armed with minute median spine. Eyestalks flattened distally, tapering to acutely or subacutely pointed distal projection, contiguous, slightly overreaching distal margin of article 1 of antennular peduncle; dorsal surface narrowly separated from rostrum, sloping anteriorly; lateral margin convex. Cornea subterminal, submedial, darkly pigmented, wider than half width of eyestalk. Antennular peduncle slightly longer than or subequal to antennal peduncle; article 1 short, hardly visible in dorsal and lateral views; article 2 shorter than article 1; article 3 2.7 times as long as article 2; articles 2 and 3 with longitudinal ventral row of sparse long setae; antennular flagella both slightly shorter than peduncle; dorsal flagellum thicker and slightly shorter than ventral flagellum. Antennal peduncle with distal two articles subcylindrical; article 4 1.9 times as long as article 5; scaphocerite minute, spiniform. Maxilliped 1 with exopod moderately broad; epipod unequally bilobed. Maxilliped 2 moderately slender; exopod short, not reaching midlength of ischium-merus. Maxilliped 3 without exopod; ischium-merus narrowly subrectangular, non-operculiform, 2.8 times as long as wide; ischium tapering, 1.8 times as long as wide, crista dentata consisting of row of 11 strong erect spines; merus about 0.5 times as long as ischium measured along dorsal margin, about 1.2 times as wide as long, wider than merus, distolateral margin obliquely truncate, unarmed; carpus cupshaped, slightly shorter than merus; propodus narrowing distally, 2.0 times as long as wide, longer than carpus; dactylus slender, digitiform, about 0.7 times as long as propodus. Pereopods 1 (chelipeds) greatly unequal, dissimilar. Male major cheliped massive, carpus-chela combined length twice carapace length. Ischium becoming rather abruptly wider distally in general contour, upper margin strongly sinuous, unarmed; lateral surface gently convex; lower margin with row of 1���5 small spines. Merus as long as ischium; upper margin slightly convex, unarmed; lateral surface forming deep concavity ventral to distinct median ridge to accommodate proximoventral margin of carpus; mesial surface generally flat; lower margin with moderately strong, bifid, forwardly directed spine proximally and row of small tubercles distal to proximal spine. Carpus subquadrate, 1.0���1.2 times as wide as long; upper and lower margins sharply carinate, smooth, proximal lower margin broadly rounded; lateral surface smooth, convex; mesial surface nearly flat. Chela 2.2. times as long as carpus; palm subquadrate, 1.4���1.6 times as long as carpus, 1.2���1.4 times as long as wide; upper margin sharply carinate, almost glabrous; lateral surface smooth, convex; mesial surface slightly convex, with small shallow depression at base of fixed finger; lower margin sharply carinate, with row of short to moderately long setae extending onto fixed finger; fixed finger 0.5���0.8 times as long as palm, gently curving, terminating in acute tip; occlusal margin smooth, unarmed; lateral surface convex, with tufts of long setae along cutting edge; mesial surface depressed along occlusal margin, with tufts of setae in proximal half. Dactylus 0.5���0.9 times as long as palm, strongly hooked distally, crossing fixed finger, with acute tip; upper surface with blunt ridge laterally and with tufts of long setae; lateral surface with longitudinal row of tufts of long setae along cutting edge; occlusal margin sinuous, unarmed or armed with 2 large, truncate teeth; mesial surface slightly elevated in midline, also with tufts of setae along cutting edge. Female major cheliped much slender than male major cheliped. Ischium armed with 1 spine on lower margin. Merus with lower margin slightly convex, unarmed. Carpus approximately twice as long as wide, widened distally. Chela 1.5 times as long as carpus. Palm 1.2 times as wide as long; no palmer process or excavation at base of fixed finger; fixed finger nearly straight. Dactylus subequal in length to palm; occlusal margin slightly sinuous, unarmed; setation of fingers less developed than in males. Minor cheliped similar in male and female, slender; carpus-chela combined length 1.1 carapace length. Ischium slightly curving; upper margin smooth, lower margin with row of 2 or 3 small spines. Merus 0.9 times as long as ischium; upper and lower margins gently convex, unarmed. Carpus wider distally, 1.8 times as long as merus, 3.3 times as long as wide; upper margin nearly straight, rounded; lower margin slightly convex, carinate. Palm slightly widened distally, 1.4 times as long as wide; upper margin nearly straight, bluntly carinate, with row of setae; lower margin sharply carinate, with row of long setae extending onto fixed finger; lateral and mesial surfaces slightly convex, smooth. Fixed finger longer than palm, slightly curving, terminating in acute tip; occlusal margin without conspicuous teeth or spines; lateral surface with row of tufts of setae along cutting edge. Dactylus 1.6 times as long as palm, as long as fixed finger; dorsal margin rounded, with row of long setae; occlusal margin unarmed. Pereopod 2 ischium short, lower distal angle produced; merus with sinuous lower margin, upper margin almost straight; carpus subtriangular, twice as long as wide; chela subtriangular; palm 1.8 times as wide as upper margin; occlusal margins of fingers bordered by thin corneous ridge; dactylus twice as long as palm. Pereopod 3 carpus subtriangular, 2.2 times as long as wide, lower margin concave, twice as long as wide; propodus suboval with produced lower proximal margin, upper margin 1.4 times width, lateral face obtusely carinate medially, lower margin convex, faintly undulate, with 1 slender spiniform seta subdistally; dactylus nearly straight, about 0.6 times as long as propodus upper margin. Pereopod 4 coxa flattened ventrally, immovable; basis and ischium partially fused, extended posterolaterally; merus longer than ischium; carpus wider distally; propodus compressed, as long as carpus, with dense grooming setae distally on lower margin, scattered stiff setae on outer surface; dactylus slightly curving, 0.3 times as long as propodus. Pereopod 5 moderately slender, with chela subequal in length to carpus, slightly curving; dactylus about 0.3 times as long as palm. Male pleopod 1 papilla-like or very small, 2-articulated, distal article (ramus) much shorter than proximal article (= peduncle). Female pleopod 1 unequally biramous; peduncle gently arcuate; endopod very small, slender, weakly arcuate; exopod longer than peduncle, with slight shoulder slightly proximal to midlength on inner margin. Male pleopod 2 absent, or very small, terminally bilobed, or distinctly biramous (rami basally fused to peduncle). Female pleopod 2 subequally biramous; peduncle strongly curved outward, inner margin angular; endopod tapering distally, slightly shorter and broader than exopod; exopod slightly curved inward. Pleopods 3���5 biramous, rami narrow; appendices internae slender, rod-like, projecting beyond mesial margin of endopod, bearing coupling hooks on apical margin. Uropod endopod and exopod subovate, overreaching posterior margin of telson. Endopod about 1.8 times as long as wide; upper surface shallowly concave in mesial half; anterior margin slightly sinuous, usually with small subdistal spine at about distal 0.2 (subdistal spine absent in female specimen); posterodistal margin convex, with fringe of setae. Exopod 1.3 times as long as wide, exceeding endopod by half length; anterior margin convex, bearing 1 small subdistal spiniform seta; posterior margin with about 10 blade-like distal setae, connected to distal margin by rounded corner; upper surface faintly slightly carinate in midline; dorsal plate extending about half distal exopod width, with distal row of stiff setae separated from setal row of distal margin. Variation. Individual variation observed in the present material is summarized in Table 1. The major cheliped exhibits strong sexual dimorphism; the male major cheliped is much heavier and more strongly armed than the female major cheliped. The male major cheliped shows also notable individual variation in the shape of the carpus and palm, and the length and armature of the dactylus, as in other callianassid taxa (e.g., Sakai 1969; Komai 2017). The ischium of the major cheliped is armed with two to five spines on the lower margin in males, while only one spine in female. The posteromedian spine on the telson is absent, or if present, minute. The development of the pleopods 1 and 2 in males also shows substantial variation not related to the size. In the male specimen (cl 3.7 mm; CBM-ZC 14140), the pleopod 1 is minute but still bi-articulate, whereas in the other four specimens (cl 3.6���3.7 mm; RUMF-ZC 04571, CBM-ZC 14141���14143), it is greatly reduced to a papilla-like bud. Three conditions are recognized in the development of the pleopod 2. In two specimens (cl 3.7 mm, CBM-ZC 14140; cl 3.7 mm, RUMF-ZC 04571), the pleopod 2 is very small but still distinctly bi-ramous (though basal articulation of each ramus is hardly recognizable); in one specimen (cl 3.7 mm; CBM-ZC 14143), it is greatly reduced to a minute, flattened piece with a bilobed terminus; in the two specimens (cl 3.6 mm, CBM-ZC 14141; cl 3.6 mm, CBM-ZC 14142, the pleopod 2 is completely absent, even a trace being not recognised. Colour in life. Carapace, pleon and tail fan generally semi-translucent, with tint of pink; cornea of eye black; major cheliped pinkish white; minor cheliped and other pereopods translucent with tint of pink (Fig. 9). Distribution. Ohura Bay, Okinawa Island, Ryukyu Islands, 3��� 23 m. Remarks. Differences between the new species and all other species in Scallasis are discussed below. Scallasis amboinae is substantially similar to S. inermis n. sp., but the possession of fewer spines on the lower margin of the major cheliped ischium (one to four versus seven), the absence of a spine on the lower margin of the minor cheliped merus (versus spine present) and the possession of few minute spiniform setae on the uropodal endopod dorsal surface (versus one of spiniform setae rather elongate) distinguish the new species from S. amboinae. Scallasis amboinae is known with certainty from Indonesia and Papua New Guinea (Bate 1888; Poore et al. 2019; this study). No information on the minor cheliped is available for S. andamaniensis. Nevertheless, the new species seems to differ from the latter species in the presence of a spiniform seta on the outer margin of the uropodal exopod (versus no spiniform seta present: Sakai 2002: fig. 24C). The chelipeds of the new species are strongly sexually dimorphic: the female major cheliped of the new species is substantially different from the cheliped of the female holotype of S. andamaniensis in the much more slender form with fewer ischium lower spines (one small spine versus four strong spines), the absence of the merus lower spine and the proportionally shorter palm being distinctly shorter than the carpus (versus subequal in length to carpus) (Fig. 6E versus Sakai 2002: fig. 25B���D). Scallasis andamaniensis is so far known only from the Andaman Sea off Thailand, at depth of 65���70 m (Sakai 2010). Ngoc-Ho (1991; as Callianassa) stated that the chelipeds of Scallasis caledonica were slightly sexually dimorphic. Scallasis inermis n. sp. is distinguished from S. caledonica by the following particulars (cf. Ngoc-Ho 1991): lower spines of the cheliped ischia are fewer in S. inermis n. sp. than in S. caledonica (one to five spines versus six to eight spines in the major side; two or three spines versus six spines in the minor side) (Figs 5A, C, 6A, E, F versus Ngoc-Ho 1991: fig. 2j, k); the spine on the lower margin of the male major cheliped is bifid in the new species (Figs 5A, 6A), rather than simple, acuminate in S. caledonica (cf. Ngoc-Ho 1991: 2 j); the female major cheliped is much less stout in S. inermis n. sp. than in S. caledonica (Fig. 6E versus Ngoc-Ho 1991: fig. 2j); the minor cheliped merus is unarmed on the lower margin in S. inermis n. sp. (Figs 5C, 6F), while there is a conspicuous spine in S. caledonica (cf. Ngoc-Ho 1991: fig. 2k); Scallasis caledonica is known only from New Caledonia, at depth of 21 m (Ngoc-Ho 1991). None of available specimens of S. contipes was intact (Sakai 2002); in particular, no information on the chelipeds is available. Nevertheless, S. inermis n. sp. can be differentiated from S. contipes by the proportionally shorter pleomere 6 (1.1 times as long as wide versus 1.3 times as long) with a lateral notch located at the posterior 1/4 (versus located at the midlength) (Fig. 4E versus Sakai 2002: fig. 35C) and the possession of one small spine on the uropodal endopod outer margin and of one small spiniform seta on the uropodal exopod outer margin (versus uropodal rami unarmed on outer margin; Sakai 2002: 35 C). Sakai (2002) did not mention on or figure spiniform setae on the uropodal endopod dorsal surface, but these could be easily overlooked. Scallasis contipes is known only from the Andaman Sea, at depths of 20���38 m (Sakai 2002). Scallasis spinophthalma is characteristic within the genus in having a sub-operculiform ischium-merus of the maxilliped 3 (Sakai 1970: text-fig. 4a; Komai et al. 2002: 9 F, G). Scallasis inermis n. sp. further differs from S. spinophthalma in the possession of a spiniform seta on the outer margin of the uropodal exopod (versus both unarmed in S. spinophthalma) (Fig. 4G versus Fig. 10D), the absence of spiniform setae on the dorsal midline of the uropodal endopod (versus there are two long spiniform setae on the dorsal midline) (Fig. 4G versus Fig. 10D) and the shape and armature of chelipeds. The ischium lower margin of either cheliped is armed with one to five small spines in S. inermis n. sp. (Figs 5A, C, 6A, E, F), rather than five to eight spines in S. spinophthalma (Sakai 1970: text-fig. 3d, e; Komai et al. 2002: fig. 10A���C; Fig 10B, C); the male major cheliped merus bears a bifid proximal spine on the lower margin in S. inermis n. sp. (Figs 5A, B, 6A, B), whereas trifid spine in S. spinophthalma (Sakai 1970: text-fig. 3d; Komai et al. 2002: fig. 10A, B); the minor cheliped merus is unarmed in S. inermis n. sp. (Figs 5C, 6F), whereas armed with one spine in S. spinophthalma (cf. Komai et al. 2002: 10 C; Fig 10C). Scallasis spinophthalma is known only from the southern area of the Sea of Japan, at depths of 84��� 210 m. The description of Scallasis tonkinae by Grebenyuk (1975) depicts: the eyestalks with a terminally located cornea and lacking the distomesial projection (Grebenyuk 1975: figs. 3���12, 3���13), relatively long pleomere 6 (1.3 times as long as wide; Grebenyuk 1975: fig. 3���16) and the distinct posteromedian concavity of the telson (Grebenyuk 1975: fig. 3���16). The unique holotype is a female, having a major cheliped being as stout as that in males of S. inermis n. sp., of which the merus bears a prominent distally bifid spine on the lower margin (Grebenyuk 1975: fig. 3���8). The female major cheliped of S. inermis n. sp. is much more slender; the merus lower margin bears only one small spine. Etymology. The specific epithet ��� inermis ��� (= unarmed) refers to the unarmed lower margin of the minor cheliped merus in the new species, which is characteristic in Scallasis., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on pages 409-416, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Sakai, K. (1969) Revision of Japanese callianassids based on the variations of larger cheliped in Callianassa petalura Stimpson and C. japonica Ortmann (Decapoda: Anomura). Publication of the Seto Marine Biological Laboratory, 17, 209 - 252.","Komai, T. (2017) Gilvossius chichijimaensis Sakai, 2015 (Crustacea: Decapoda: Axiidea: Callianassidae), a junior subjective synonym of Paratrypaea bouvieri (Nobili, 1904). Zootaxa, 4291 (2), 391 - 395. https: // doi. org / 10.11646 / zootaxa. 4291.2.11","Bate, S. C. (1888) Report on the Crustacea Macrura collected by H. M. S. Challenger during the years 1873 - 76. Report on the Scientific Results of the Voyage of H. M. S. \" Challenger \" during the Years 1873 - 76, Zoology, 24 (i-xc), 1 - 942, pls. 1 - 157.","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05","Sakai, K. (2002) Callianassidae (Decapoda, Thalassinidea) in the Andaman Sea, Thailand. Phuket Marine Biological Center Special Publication, 23, 461 - 532.","Sakai, K. (2010) Callianassoidea from the Gulf of Tonkin and the Red sea, in the Zoological Museum of Moscow University (Decapoda, Thalassinidea). Crustaceana, 83, 1431 - 1467. https: // doi. org / 10.1163 / 001121610 X 538174","Ngoc-Ho, N. (1991) Sur quelques Callianassidae et Upogebiidae de Nouvelle Caledonie (Crustacea, Thalassinidea). In: Richer de Forges, B. (Ed.), Le benthos des fonds meubles des lagons de Nouvelle Caledonie. Vol. 1. ORSTOM Editions, Paris, pp. 281 - 311.","Sakai, K. (1970) A small collection of the thalassinideans from the waters around Tsushima Islands, Japan, including a new species of Callianassa (Crustacea, Anomura). Publications of the Seto Marine Biological Laboratory, 28 (1), 37 - 47. https: // doi. org / 10.5134 / 175621","Komai, T., Ohtsuka, S., Nakaguchi, K. & Go, A. (2002) Decapod crustaceans collected from the southern part of the Sea of Japan in 2000 - 2001 using TRV Toyoshio-maru. Natural History Research, 7 (1), 19 - 73.","Grebenyuk, L. P. (1975) Dva novykh vida desyatinogikh rakoobraznykh nadsemeistva Thalassinidea [Two new decapod species of the superfamily Thalassinidea]. Zoologischeskii Zhurnal, 54, 299 - 304."]}

Scallasis contipes (Sakai, 2002) Callianassa contipes Sakai 2002: 523���525, fig 35.��� Sakai 2005: 80. Cheramus contipes.��� Sakai 2011a: 367. Scallasis contipes.��� Poore et al. 2019: 143. Type locality. Andaman Sea, 07��30���N 098��57���E, 20��� 38 m. Diagnosis. Pleomere 6 1.3 times as long as wide, with lateral notches at about midlength. Telson 0.8 times as long as wide; greatest width 1.1 times posterior width. Maxilliped 3 ischium-merus 3.5 times as long as wide; merus free distal margin oblique. Distribution. Presently known only from the type locality in the Andaman Sea. Remarks. Scallasis contipes was originally described on the basis of four female specimens, one ovigerous, and two supplemental specimens (also female); none was intact. The rostrum, eyestalks and maxilliped 3 are typical of the genus. Chelipeds are unknown and Sakai���s (2002) figures do not show spiniform setae or marginal tooth on the uropodal rami, but this might be an omission. The telson appears to taper only slightly. Sakai (2002) separated Scallasis contipes from S. andamaniensis on an obliquely truncate distal margin on maxilliped 3 (vs truncate). Both were collected in the Andaman Sea, S. contipes at shallower depths., Published as part of Komai, Tomoyuki, Poore, Gary C. B. & Fujita, Yoshihisa, 2020, Redescription of the poorly known ghost shrimp species, Scallasis amboinae Bate, 1888, review of the genus, and description of a new species from the Ryukyu Islands, Japan (Decapoda: Axiidea: Callianassidae), pp. 401-420 in Zootaxa 4766 (3) on page 408, DOI: 10.11646/zootaxa.4766.3.1, http://zenodo.org/record/3765527, {"references":["Sakai, K. (2002) Callianassidae (Decapoda, Thalassinidea) in the Andaman Sea, Thailand. Phuket Marine Biological Center Special Publication, 23, 461 - 532.","Sakai, K. (2005) Callianassoidea of the world (Decapoda, Thalassinidea). Crustaceana Monographs, 4, 1 - 285.","Sakai, K. (2011 a) Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs, 13, 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Poore, G. C. B., Dworschak, P. C., Robles, R., Mantelatto, F. L. & Felder, D. L. (2019) A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support. Memoirs of Museum Victoria, 78, 73 - 146. https: // doi. org / 10.24199 / j. mmv. 2019.78.05"]}

Scallasis inermis n. sp. [New Japanese name: Mame-sunamoguri] (Figs 4–9) http://zoobank.org/ urn:lsid:zoobank.org:act: 68C54DF6-7729-4E82-8785-87AAD5CC1A14 Type material. Holotype: Japan, Okinawa Island, Ohura Bay, Umi-saboten diving point (stn D1), 3–20 m, 18 June 2009, SCUBA diving, yabby pump, male (cl 3.7 mm; photographed), coll. Y. Fujita and T. Naruse, CBM-ZC 14140. Paratypes: Japan, Okinawa Island, Ohura B ay, Tettou-oki diving point, 23 m, muddy sand, 9 November 2013, SCUBA diving, yabby pump, coll. Y. Fujita, 1 male (cl 3.7 mm; photographed), RUMF-ZC-04571; same data, 3 males (cl 3.6, 3.6, 3.7 mm), 1 ovigerous female (cl 3.6 mm), CBM-ZC 14141–14144. Diagnosis. Pleomere 6 1.1 times as long as wide. Telson 1 times as long as wide; greatest width 1.5 times posterior width. Maxilliped 3 ischium-merus 2.6 times as long as wide; merus free distal margin oblique. Female major cheliped ischium lower margin with 1–5 small spines; merus lower margin unarmed; palm 0.7 times as long as carpus. Male major cheliped merus lower margin with bifid proximal spine; palm 1.4–1.6 as long as carpus; dactylus with 2 notches on cutting margin. Minor cheliped ischium lower margin with 2 or 3 small spines; merus lower margin unarmed. Male pleopod 1 of 1 minute article, or of 2 small articles. Male pleopod 2 biramous. Uropodal endopod anterior margin with small spine about two-thirds along; dorsal surface with 1–3 minute proximal spiniform setae; exopod anterior margin with small spiniform seta about three-quarters along. Description. Rostrum narrowly triangular, spiniform, directed forward, with slight ventral carina, falling slightly short of distal ends of eyestalks. Carapace subequal in length to pleomeres 1 and 2 combined; orbital margins concave; anterolateral projections triangular with subacute tip; excavation inferior to anterolateral projections deep, U-shaped; deep cervical groove across 0.8 length of carapace, without postrostral transverse groove; linea thalassinica distinct, extending to posterolateral margin of carapace. Thoracic sternite 7 subpentagonal with slightly projecting anteromedian margin; ventral surface with shallow median groove. Pleomere 1 narrowing anteriorly in dorsal view; pleuron with poorly defined ventral margin. Pleomere 2 pleuron posterolateral margin slightly expanded, without tuft of setae. Pleomeres 3–5 pleura each with patch of plumose setae; posterolateral margins slightly expanded; pleuron 3 with tuft of long setae adjacent to posterolateral margin, pleura 4 and 5 with tuft or longitudinal row of setae on posterior parts, respectively. Pleomere 6 about 1.1 times as long as wide, subquadrate, slightly narrowing posteriorly, lacking ventrolateral projection; lateral margin with shallow notch at about posterior 0.2. Telson trapezoidal, narrowing posteriorly, approximately as long as wide, broadest at anterior 0.2; greatest width 1.5 times posterior width; dorsal surface medially with some spiniform setae in short transverse row anterior to midlength; lateral margin unarmed; 2 pairs of small spiniform setae at rounded posterolateral angles; posterior margin shallowly concave medially, unarmed or armed with minute median spine. Eyestalks flattened distally, tapering to acutely or subacutely pointed distal projection, contiguous, slightly overreaching distal margin of article 1 of antennular peduncle; dorsal surface narrowly separated from rostrum, sloping anteriorly; lateral margin convex. Cornea subterminal, submedial, darkly pigmented, wider than half width of eyestalk. Antennular peduncle slightly longer than or subequal to antennal peduncle; article 1 short, hardly visible in dorsal and lateral views; article 2 shorter than article 1; article 3 2.7 times as long as article 2; articles 2 and 3 with longitudinal ventral row of sparse long setae; antennular flagella both slightly shorter than peduncle; dorsal flagellum thicker and slightly shorter than ventral flagellum. Antennal peduncle with distal two articles subcylindrical; article 4 1.9 times as long as article 5; scaphocerite minute, spiniform. Maxilliped 1 with exopod moderately broad; epipod unequally bilobed. Maxilliped 2 moderately slender; exopod short, not reaching midlength of ischium-merus. Maxilliped 3 without exopod; ischium-merus narrowly subrectangular, non-operculiform, 2.8 times as long as wide; ischium tapering, 1.8 times as long as wide, crista dentata consisting of row of 11 strong erect spines; merus about 0.5 times as long as ischium measured along dorsal margin, about 1.2 times as wide as long, wider than merus, distolateral margin obliquely truncate, unarmed; carpus cupshaped, slightly shorter than merus; propodus narrowing distally, 2.0 times as long as wide, longer than carpus; dactylus slender, digitiform, about 0.7 times as long as propodus. Pereopods 1 (chelipeds) greatly unequal, dissimilar. Male major cheliped massive, carpus-chela combined length twice carapace length. Ischium becoming rather abruptly wider distally in general contour, upper margin strongly sinuous, unarmed; lateral surface gently convex; lower margin with row of 1–5 small spines. Merus as long as ischium; upper margin slightly convex, unarmed; lateral surface forming deep concavity ventral to distinct median ridge to accommodate proximoventral margin of carpus; mesial surface generally flat; lower margin with moderately strong, bifid, forwardly directed spine proximally and row of small tubercles distal to proximal spine. Carpus subquadrate, 1.0–1.2 times as wide as long; upper and lower margins sharply carinate, smooth, proximal lower margin broadly rounded; lateral surface smooth, convex; mesial surface nearly flat. Chela 2.2. times as long as carpus; palm subquadrate, 1.4–1.6 times as long as carpus, 1.2–1.4 times as long as wide; upper margin sharply carinate, almost glabrous; lateral surface smooth, convex; mesial surface slightly convex, with small shallow depression at base of fixed finger; lower margin sharply carinate, with row of short to moderately long setae extending onto fixed finger; fixed finger 0.5–0.8 times as long as palm, gently curving, terminating in acute tip; occlusal margin smooth, unarmed; lateral surface convex, with tufts of long setae along cutting edge; mesial surface depressed along occlusal margin, with tufts of setae in proximal half. Dactylus 0.5–0.9 times as long as palm, strongly hooked distally, crossing fixed finger, with acute tip; upper surface with blunt ridge laterally and with tufts of long setae; lateral surface with longitudinal row of tufts of long setae along cutting edge; occlusal margin sinuous, unarmed or armed with 2 large, truncate teeth; mesial surface slightly elevated in midline, also with tufts of setae along cutting edge. Female major cheliped much slender than male major cheliped. Ischium armed with 1 spine on lower margin. Merus with lower margin slightly convex, unarmed. Carpus approximately twice as long as wide, widened distally. Chela 1.5 times as long as carpus. Palm 1.2 times as wide as long; no palmer process or excavation at base of fixed finger; fixed finger nearly straight. Dactylus subequal in length to palm; occlusal margin slightly sinuous, unarmed; setation of fingers less developed than in males. Minor cheliped similar in male and female, slender; carpus-chela combined length 1.1 carapace length. Ischium slightly curving; upper margin smooth, lower margin with row of 2 or 3 small spines. Merus 0.9 times as long as ischium; upper and lower margins gently convex, unarmed. Carpus wider distally, 1.8 times as long as merus, 3.3 times as long as wide; upper margin nearly straight, rounded; lower margin slightly convex, carinate. Palm slightly widened distally, 1.4 times as long as wide; upper margin nearly straight, bluntly carinate, with row of setae; lower margin sharply carinate, with row of long setae extending onto fixed finger; lateral and mesial surfaces slightly convex, smooth. Fixed finger longer than palm, slightly curving, terminating in acute tip; occlusal margin without conspicuous teeth or spines; lateral surface with row of tufts of setae along cutting edge. Dactylus 1.6 times as long as palm, as long as fixed finger; dorsal margin rounded, with row of long setae; occlusal margin unarmed. Pereopod 2 ischium short, lower distal angle produced; merus with sinuous lower margin, upper margin almost straight; carpus subtriangular, twice as long as wide; chela subtriangular; palm 1.8 times as wide as upper margin; occlusal margins of fingers bordered by thin corneous ridge; dactylus twice as long as palm. Pereopod 3 carpus subtriangular, 2.2 times as long as wide, lower margin concave, twice as long as wide; propodus suboval with produced lower proximal margin, upper margin 1.4 times width, lateral face obtusely carinate medially, lower margin convex, faintly undulate, with 1 slender spiniform seta subdistally; dactylus nearly straight, about 0.6 times as long as propodus upper margin. Pereopod 4 coxa flattened ventrally, immovable; basis and ischium partially fused, extended posterolaterally; merus longer than ischium; carpus wider distally; propodus compressed, as long as carpus, with dense grooming setae distally on lower margin, scattered stiff setae on outer surface; dactylus slightly curving, 0.3 times as long as propodus. Pereopod 5 moderately slender, with chela subequal in length to carpus, slightly curving; dactylus about 0.3 times as long as palm. Male pleopod 1 papilla-like or very small, 2-articulated, distal article (ramus) much shorter than proximal article (= peduncle). Female pleopod 1 unequally biramous; peduncle gently arcuate; endopod very small, slender, weakly arcuate; exopod longer than peduncle, with slight shoulder slightly proximal to midlength on inner margin. Male pleopod 2 absent, or very small, terminally bilobed, or distinctly biramous (rami basally fused to peduncle). Female pleopod 2 subequally biramous; peduncle strongly curved outward, inner margin angular; endopod tapering distally, slightly shorter and broader than exopod; exopod slightly curved inward. Pleopods 3–5 biramous, rami narrow; appendices internae slender, rod-like, projecting beyond mesial margin of endopod, bearing coupling hooks on apical margin. Uropod endopod and exopod subovate, overreaching posterior margin of telson. Endopod about 1.8 times as long as wide; upper surface shallowly concave in mesial half; anterior margin slightly sinuous, usually with small subdistal spine at about distal 0.2 (subdistal spine absent in female specimen); posterodistal margin convex, with fringe of setae. Exopod 1.3 times as long as wide, exceeding endopod by half length; anterior margin convex, bearing 1 small subdistal spiniform seta; posterior margin with about 10 blade-like distal setae, connected to distal margin by rounded corner; upper surface faintly slightly carinate in midline; dorsal plate extending about half distal exopod width, with distal row of stiff setae separated from setal row of distal margin. Variation. Individual variation observed in the present material is summarized in Table 1. The major cheliped exhibits strong sexual dimorphism; the male major cheliped is much heavier and more strongly armed than the female major cheliped. The male major cheliped shows also notable individual variation in the shape of the carpus and palm, and the length and armature of the dactylus, as in other callianassid taxa (e.g., Sakai 1969; Komai 2017). The ischium of the major cheliped is armed with two to five spines on the lower margin in males, while only one spine in female. The posteromedian spine on the telson is absent, or if present, minute. The development of the pleopods 1 and 2 in males also shows substantial variation not related to the size. In the male specimen (cl 3.7 mm; CBM-ZC 14140), the pleopod 1 is minute but still bi-articulate, whereas in the other four specimens (cl 3.6–3.7 mm; RUMF-ZC 04571, CBM-ZC 14141–14143), it is greatly reduced to a papilla-like bud. Three conditions are recognized in the development of the pleopod 2. In two specimens (cl 3.7 mm, CBM-ZC 14140; cl 3.7 mm, RUMF-ZC 04571), the pleopod 2 is very small but still distinctly bi-ramous (though basal articulation of each ramus is hardly recognizable); in one specimen (cl 3.7 mm; CBM-ZC 14143), it is greatly reduced to a minute, flattened piece with a bilobed terminus; in the two specimens (cl 3.6 mm, CBM-ZC 14141; cl 3.6 mm, CBM-ZC 14142, the pleopod 2 is completely absent, even a trace being not recognised. Colour in life. Carapace, pleon and tail fan generally semi-translucent, with tint of pink; cornea of eye black; major cheliped pinkish white; minor cheliped and other pereopods translucent with tint of pink (Fig. 9). Distribution. Ohura Bay, Okinawa Island, Ryukyu Islands, 3– 23 m. Remarks. Differences between the new species and all other species in Scallasis are discussed below. Scallasis amboinae is substantially similar to S. inermis n. sp., but the possession of fewer spines on the lower margin of the major cheliped ischium (one to four versus seven), the absence of a spine on the lower margin of the minor cheliped merus (versus spine present) and the possession of few minute spiniform setae on the uropodal endopod dorsal surface (versus one of spiniform setae rather elongate) distinguish the new species from S. amboinae. Scallasis amboinae is known with certainty from Indonesia and Papua New Guinea (Bate 1888; Poore et al. 2019; this study). No information on the minor cheliped is available for S. andamaniensis. Nevertheless, the new species seems to differ from the latter species in the presence of a spiniform seta on the outer margin of the uropodal exopod (versus no spiniform seta present: Sakai 2002: fig. 24C). The chelipeds of the new species are strongly sexually dimorphic: the female major cheliped of the new species is substantially different from the cheliped of the female holotype of S. andamaniensis in the much more slender form with fewer ischium lower spines (one small spine versus four strong spines), the absence of the merus lower spine and the proportionally shorter palm being distinctly shorter than the carpus (versus subequal in length to carpus) (Fig. 6E versus Sakai 2002: fig. 25B–D). Scallasis andamaniensis is so far known only from the Andaman Sea off Thailand, at depth of 65–70 m (Sakai 2010). Ngoc-Ho (1991; as Callianassa) stated that the chelipeds of Scallasis caledonica were slightly sexually dimorphic. Scallasis inermis n. sp. is distinguished from S. caledonica by the following particulars (cf. Ngoc-Ho 1991): lower spines of the cheliped ischia are fewer in S. inermis n. sp. than in S. caledonica (one to five spines versus six to eight spines in the major side; two or three spines versus six spines in the minor side) (Figs 5A, C, 6A, E, F versus Ngoc-Ho 1991: fig. 2j, k); the spine on the lower margin of the male major cheliped is bifid in the new species (Figs 5A, 6A), rather than simple, acuminate in S. caledonica (cf. Ngoc-Ho 1991: 2 j); the female major cheliped is much less stout in S. inermis n. sp. than in S. caledonica (Fig. 6E versus Ngoc-Ho 1991: fig. 2j); the minor cheliped merus is unarmed on the lower margin in S. inermis n. sp. (Figs 5C, 6F), while there is a conspicuous spine in S. caledonica (cf. Ngoc-Ho 1991: fig. 2k); Scallasis caledonica is known only from New Caledonia, at depth of 21 m (Ngoc-Ho 1991). None of available specimens of S. contipes was intact (Sakai 2002); in particular, no information on the chelipeds is available. Nevertheless, S. inermis n. sp. can be differentiated from S. contipes by the proportionally shorter pleomere 6 (1.1 times as long as wide versus 1.3 times as long) with a lateral notch located at the posterior 1/4 (versus located at the midlength) (Fig. 4E versus Sakai 2002: fig. 35C) and the possession of one small spine on the uropodal endopod outer margin and of one small spiniform seta on the uropodal exopod outer margin (versus uropodal rami unarmed on outer margin; Sakai 2002: 35 C). Sakai (2002) did not mention on or figure spiniform setae on the uropodal endopod dorsal surface, but these could be easily overlooked. Scallasis contipes is known only from the Andaman Sea, at depths of 20–38 m (Sakai 2002). Scallasis spinophthalma is characteristic within the genus in having a sub-operculiform ischium-merus of the maxilliped 3 (Sakai 1970: text-fig. 4a; Komai et al. 2002: 9 F, G). Scallasis inermis n. sp. further differs from S. spinophthalma in the possession of a spiniform seta on the outer margin of the uropodal exopod (versus both unarmed in S. spinophthalma) (Fig. 4G versus Fig. 10D), the absence of spiniform setae on the dorsal midline of the uropodal endopod (versus there are two long spiniform setae on the dorsal midline) (Fig. 4G versus Fig. 10D) and the shape and armature of chelipeds. The ischium lower margin of either cheliped is armed with one to five small spines in S. inermis n. sp. (Figs 5A, C, 6A, E, F), rather than five to eight spines in S. spinophthalma (Sakai 1970: text-fig. 3d, e; Komai et al. 2002: fig. 10A–C; Fig 10B, C); the male major cheliped merus bears a bifid proximal spine on the lower margin in S. inermis n. sp. (Figs 5A, B, 6A, B), whereas trifid spine in S. spinophthalma (Sakai 1970: text-fig. 3d; Komai et al. 2002: fig. 10A, B); the minor cheliped merus is unarmed in S. inermis n. sp. (Figs 5C, 6F), whereas armed with one spine in S. spinophthalma (cf. Komai et al. 2002: 10 C; Fig 10C). Scallasis spinophthalma is known only from the southern area of the Sea of Japan, at depths of 84– 210 m. The description of Scallasis tonkinae by Grebenyuk (1975) depicts: the eyestalks with a terminally located cornea and lacking the distomesial projection (Grebenyuk 1975: figs. 3–12, 3–13), relatively long pleomere 6 (1.3 times as long as wide; Grebenyuk 1975: fig. 3–16) and the distinct posteromedian concavity of the telson (Grebenyuk 1975: fig. 3–16). The unique holotype is a female, having a major cheliped being as stout as that in males of S. inermis n. sp., of which the merus bears a prominent distally bifid spine on the lower margin (Grebenyuk 1975: fig. 3–8). The female major cheliped of S. inermis n. sp. is much more slender; the merus lower margin bears only one small spine. Etymology. The specific epithet “ inermis ” (= unarmed) refers to the unarmed lower margin of the minor cheliped merus in the new species, which is characteristic in Scallasis.

Paraxiopsis brocki (De Man, 1888) Figs 2c, d, 6c–g Axius brocki De Man, 1888: 475, pl. 20 fig. 3. Axiopsis (Paraxiopsis) brocki .— De Man, 1905: 597.— Tirmizi, 1983: 88–90, fig. 3. Eutrichocheles brocki.— Sakai and de Saint Laurent,1989: 52, fig. 4B.— Ngoc-Ho, 1998: 365–368, fig. 1. Paraxiopsis brocki.— Kensley, 1996.— Poore and Collins, 2009: 266.— Sakai, 2011: 158–161, fig. 27C (full synonymy). Material examined. Papua New Guinea. Madang Province, PAPUA NIUGINI stations. W of Panab I., 05° 10.3' S, 145° 48.5'E, 1–18 m (stn PR147), IU-2013-7108 (male, 6.8 mm). Riwo, mangrove, 05° 09' S, 145° 48.2' E, 1–2 m (stn PR235), IU-2013-7118 (ovigerous female, 5.5 mm). Kranket I., Cape Jantzen, 05° 12.5' S, 145° 49.1' E, 13 m (stn PB11), IU-2013-7126 (male, 3.1 mm). New Ireland Province, Kavieng region, KAVIENG 2014 stations. S coast of Baudison I., 02° 45.2' S, 150° 41.7' E, 22–27 m (stn KB68), IU-2014-990 (female, 5.5 mm); IU-2014-1032 (female, 5.9 mm). NW point of Nusa I., 02° 33.9' S, 150° 46.7' E, 15–17 m (stn KB04), IU-2014-2054 (juvenile, 3.1 mm). Marthas Shoal, sand and coarse rubble in gutter, 20 m, 02° 32.5' S, 150° 35.3' E (stn KB60), NMV J71640 (male, 7.5 mm; 2 ovigerous females, 6.8 mm); IU-2014-2736 (male, 6.8 mm). NW point of Nubis I., 02° 37.2' S, 150° 31.8' E, 20 m (stn KB39), IU-2014-17693 (juvenile, damaged). Indonesia. Maluku Province, Pulau Wuliaru, 7° 27' S, 131° 3.7' E, IU-2014-12081 (female, 9.5 mm). Diagnosis. Carapace smooth, without tomentum of setae. Rostrum with 4–6 lateral teeth; lateral gastric carina with supraorbital spine plus 2 teeth; submedian gastric carina with 1 or 2 teeth; median gastric carina without spines. Telson with 3 or 4 pairs of dorsal spines. Cheliped merus with 1–3 spines on upper margin, palm unornamented. Male pleopod 1 absent in small specimens, single article in adults. Distribution. Widespread in the Indo West-Pacific, from eastern Africa, Western Australia, northern Australia, to southern Japan and French Polynesia; to 91 m depth (Sakai, 2011). Remarks. The new material contributes little to knowledge of this widespread and frequently taken species. The species was well illustrated by Ngoc-Ho (1998). Sakai (2011: fig. 27C) figured a simple male pleopod 1 on a male from Darwin, Australia; pleopod 1 is absent in the smallest male and minute in the larger ones from this collection. Most of the specimens at hand have a minute anterior tooth on pleonal pleura 2–5. Sakai (2011) himself discussed variation in this character and in the presence or absence of the male pleopod 1 after presenting an extensive diagnosis., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on page 11, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Man, J. G. de 1888. Bericht uber die von Herrn Dr. J. Brock im indischen Archipel gesammelten Decapoden und Stomatopoden. Archiv fur Naturgeschichte 53: 215 - 600, pls 7 - 22. http: // biodiversitylibrary. org / page / 6379410","Man, J. G. de 1905. Diagnoses of new species of macrurous decapod Crustacea from the \" Siboga-Expedition \". Tijdschrift der Nederlandsche Dierkundige Vereeniging 9: 587 - 614. http: // biodiversitylibrary. org / page / 9779712","Tirmizi, N. M. 1983. Four axiids (Decapoda, Thalassinidea) from Indonesia. Researches on Crustacea, Carcinological Society of Japan 12: 85 - 95. http: // doi. org / 10.18353 / rcustacea. 12.0 _ 85","Sakai, K., and de Saint Laurent, M. 1989. A check list of Axiidae (Decapoda, Crustacea, Thalassinidea, Anomula), with remarks and in addition descriptions of one new subfamily, eleven new genera and two new species. Naturalists, Publications of Tokushima Biological Laboratory, Shikoku University 3: 1 - 104.","Ngoc-Ho, N. 1998. Le genre Eutrichocheles Wood-Mason, 1876 (Crustacea, Decapoda, Thalassinidea) en Polynesie francaise et au Vietnam avec description de deux especes nouvelles. Zoosystema 20: 363 - 378.","Kensley, B. 1996. The genus Paraxiopsis De Man, with descriptions of new species from the Western Atlantic (Crustacea: Decapoda: Axiidae). Bulletin of Marine Science 58: 709 - 729. https: // repository. si. edu / handle / 10088 / 10979","Poore, G. C. B., and Collins, D. J. 2009. Australian Axiidae (Crustacea: Decapoda: Axiidea). Memoirs of Museum Victoria 66: 221 - 287. http: // doi. org / 10.24199 / j. mmv. 2009.66.20","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616."]}

Allaxiopsis picteti (Zehntner, 1894) Figs 1c, 4 Paraxius picteti Zehntner, 1894: 196–199, pl. 9 fig. 25. ? Axiopsis picteti.— Borradaile, 1903: 539. Axiopsis (Axiopsis) picteti .— De Man, 1925: 6, 70, 92–96, pl. 7 fig. 16. Allaxius picteti. — Sakai and de Saint Laurent, 1989: 75.— Kensley, 2003: 361, pls 5, 6. Allaxiopsis picteti.— Sakai, 2011: 39–40. Material examined. Papua New Guinea. Madang Province. PAPUA NIUGINI stations. S of Urembo I., outer slope, 05° 15.9' S, 145° 47.1' E, 3 m (stn PB43), IU-2013-1209 (male, 8.3 mm). N of Bil Bil I., 05° 17.7'S, 145° 46.9' E, 5 m (stn PB51), IU-2013-7014 (male, 2.5 mm). New Ireland Province, Kavieng lagoon, KAVIENG 2014 stations. S side of Patio I., 02° 36.2' S, 150° 31.6'E, 6–8 m (stn KB38), IU-2014- 2526 (male, 6.8 mm). NW point of Nusa I., 02° 33.9' S, 150° 46.7' E, 8–10 m (stn KS3), IU-2014-2041 (female, 2.0 mm). Australia. Western Australia, Kimberleys, Echuca Shoal, Type locality. Ambon, Indonesia. Diagnosis. Major cheliped, propodus with blunt tubercles on lateral and mesial faces, more prominent nearer upper margin. Minor cheliped, propodus tuberculate on lateral and mesial faces. Supplementary description. Rostrum acute, depressed, 0.3 length of rostral base–cervical groove, with pair of erect lateral spines near apex and larger pair at base. Gastric carina difficult to differentiate; median gastric carina obsolete except near base of rostrum, with sequence of 1, 1, 2, 2, 2 teeth; submedian gastric carina obsolete, with 1 tooth anteriorly and 2 or 3 teeth posteriorly; supraocular spine oblique, not marginal; lateral gastric carina with 2 or 3 blunt teeth. Eyestalk reaching beyond end of rostrum. Antenna article 2 with small distal spine; scaphocerite 4 times as long as greatest height (lateral view), reaching third length of article 4. Major cheliped coxa–carpus unarmed; propodus upper margin 1.4 times greatest height, carinate, with 5 spines, lateral face tuberculate proximally near upper margin; fixed finger 0.5 times length of upper margin of propodus, cutting edge with 2 blunt distal teeth; dactylus cutting edge with 3 low rounded teeth in proximal half.Minor cheliped coxa–carpus unarmed; propodus upper margin 1.5 times greatest height, carinate, with 2 distal spines, lateral face with few proximal tubercles; fixed finger almost as long as upper margin of propodus, with distal teeth near tip of cutting edge; dactylus cutting edge smooth. Telson 1.4 times as wide as long at level of most anterior lateral teeth; distal margin 0.8 times telson greatest width; lateral margin with 3 teeth; distal margin straight, with 1 lateral articulating robust seta, lateral fixed spine, with median spine; face with 2 pairs of spines. Uropodal endopod 1.6 times as long as wide; anterior margin strongly lobed proximally (as rounded shoulder), otherwise concave with or without spine at midpoint, with subdistal and distal spine; posterior margin convex, with 5 spines along distal third; distal margin straight, transverse, with depressed spine at anterior end, 2 marginal spines, 1 stronger spine and another superior, at posterior end; facial rib unarmed. Uropodal exopod semicircular, 1.5 times as long as wide; anterior margin of article 1 convex, with 5 or 6 marginal teeth, 1 submarginal; posterior margin straight, with 3 distal spines set obliquely; distal margin transverse, 3 marginal spines, strong articulating spine near anterior corner; article 2 with 5 teeth along distal margin. Colour. Carapace high red-brown; pleon with patches of greenbrown and scattered red chromatophores; antennal flagellum with alternating white and brown stripes; cheliped high blue; pereopods with transverse blue bands on major articles, otherwise white. Distribution. Indonesia: Ambon (type locality), Kabaena I., Sulawesi (De Man, 1925); Guam; Marshall Islands; Fiji (Kensley, 2003); Papua New Guinea: Madang, Bougainville, New Ireland; Australia, N Western Australia; 3–20 m depth. Remarks. Kensley (2003) reported on material from Guam and included a photograph with colours similar to the one here. Kensley also reported on unpublished records of the species from Papua New Guinea, Fiji and the Marshall Islands identified by him (see USNM online database http://collections. nmnh.si.edu/search/iz/). Kensley’s record of the species from Malaysia is not on the database. The carapace, tail fan and the never-before-illustrated chelipeds are figured here., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on pages 4-6, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Zehntner, L. 1894. Voyage de M. M. Bedot et C. Pictet dans l'Archipel Malais. Crustaces de l'Archipel Malais. Revue Suisse de Zoologie 2: 135 - 214. http: // biodiversitylibrary. org / page / 9970404","Borradaile, L. A. 1903. On the classification of the Thalassinidea. Annals and Magazine of Natural History (ser. 7) 12: 534 - 551 + Addendum on p. 638. http: // biodiversitylibrary. org / page / 29993300","Man, J. G. de 1925. The Decapoda of the Siboga-Expedition. Part VI. The Axiidae collected by the Siboga-Expedition. Siboga Expeditie Monographie 39 a 5: 1 - 127. http: // decapoda. nhm. org / pdfs / 15372 / 15372. pdf","Sakai, K., and de Saint Laurent, M. 1989. A check list of Axiidae (Decapoda, Crustacea, Thalassinidea, Anomula), with remarks and in addition descriptions of one new subfamily, eleven new genera and two new species. Naturalists, Publications of Tokushima Biological Laboratory, Shikoku University 3: 1 - 104.","Kensley, B. 2003. Axioid shrimps from Guam (Crustacea, Decapoda, Thalassinidea). Micronesica 35 - 36: 359 - 384. https: // repository. si. edu / handle / 10088 / 10970","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616.","Man, J. G. de 1888. Bericht uber die von Herrn Dr. J. Brock im indischen Archipel gesammelten Decapoden und Stomatopoden. Archiv fur Naturgeschichte 53: 215 - 600, pls 7 - 22. http: // biodiversitylibrary. org / page / 6379410"]}

Neaxius capricornicus sp. nov. (http://zoobank.org/urn:lsid:zoobank.org:act:0FEDB7A0-7265- 4E5B-A26D-861FFFB7F7B6) Figures 6, 8g –l Axius (Neaxius) glyptocercus.— Poore and Griffin, 1979: 236–238 (partim), figs 8g –i. Neaxius glyptocercus.— Tudge and Cunningham, 2002: 841.— Tsang et al., 2008: 218–219.— Robles et al., 2009: 316.— Sakai, 2011: 326–331 (partim) figs 62A, B, E. Material examined. Holotype. Australia, Qld, North Stradbroke I., Deanbilla Bay, Dunwich, 27° 30' S, 153° 24' E, NMV J39643 (female, 26 mm; see Tudge and Cunningham [2002]), Paratypes. Collected with holotype. NMV J71641 (female, 23 mm); NMV J40714 (2 females, 26 mm; male, 21 mm). Australia, Qld, North Stradbroke I., Dunwich, 27° 30' S, 153° 24' E, AM P.13723 (male, 27 mm). Capricorn Group, North West I., 23° 18' S, 151° 42' E, AM P.10060 (female, 38 mm), AM P.11829 (female, 30 mm). Other material. Fiji, Viti Levu, ZMH K8392 (Godeffroy No. 7430) (Sakai, 2011: fig. 62A, E) (male, 14.3 mm). French Polynesia, Tahiti. ZMH 41226 (Sakai, 2011: fig. 62B) (male, 27 mm). Diagnosis. Carapace supra-antennal margin with anteriorly directed spine; anterolateral margin with 6 (5–7) spines, dorsalmost anterolaterally directed; branchiostegite anterior margin with 1 spine; cervical groove without spines along posterior margin. Telson 1.3–1.5 times as wide as long; tapering from widest point to posterior margin; anterior transverse ridge straight, curving laterally to reach lateral margin at its widest point; posterior transverse ridge situated at 0.5 distance between first transverse ridge and posterior margin, ends sharply rounded, almost overhanging; lateral margin with 0–2 marginal teeth; posterior face concave, with shallow median groove, smooth sublaterally. Antenna article 2 without upper-mesial spine, without lateral spine; scaphocerite with 1 mesial sharp spine, 2 (1–4) sharp ventral spines; article 4 lower margin without spines. Cheliped merus, lower margin with 5 (4–6) spines, distolateral face with row of 4 (3–5) spines. Pereopod 2 merus, lower margin with 6 (3–11) spines. Pereopod 3 merus, lower margin with 8 (4–12) spines. Supplementary description of holotype. Rostrum with 5 pairs of erect blunt spines; sharp hiatus before smooth lateral carina; median carina with 5 tubercles; anterior gastric region rugose; cervical groove defined posteriorly by sharp carina; branchiostegal groove separating smooth cardiac region from punctate branchiostegal region. Anterolateral margin with 6 spines on right, 5 on left, first flaring laterally, longer gap between third and fourth, between fifth and sixth; anterior branchiostegal margin with 1 short spine. Pleomere 1 pleuron with 3 tubercles; pleomere 2 with 7 tubercles. Telson 1.35 times as wide as long; widest at prominent lateral lobes, at c. 0.4 of length; tapering sharply then gradually from widest point to posterior margin; posterior margin c. 0.6 times greatest width; anterior transverse ridge at c. 0.25 length, straight, curving laterally to reach lateral margin at its widest point; posterior transverse ridge situated at 0.5 distance between first transverse ridge and posterior margin, ends sharply rounded, almost overhanging; lateral margin without marginal teeth; posterior face concave, with shallow median groove, smooth sublaterally. Antenna article 2 without mesial spine, without lateral spine; scaphocerite with 1 mesial sharp spine, 3 sharp ventral spines; article 4 lower margin without spines. Maxilliped 3 merus with 1 short, 2 longer distal spines. Cheliped coxa with 2 spines; basis with 1 spine; ischium with 3 spines; merus, lower margin with 4 spines on right, 5 on left, distolateral face with row of 3 spines, upper margin with 4 spines; carpus lower margin with 1 distal spine. Pereopod 2 coxa with 2 spines; basis with 2 spines; ischium with 3 spines; merus, lower margin with 7 spines on right, 6 on left, more proximal one minute. Pereopod 3 coxa with 2 spines; basis with 2 spines; ischium without spines; merus, lower margin spines in 2 rows: 6 spines mesially, last 3 minute, 6 laterally, last minute. Pereopods 4 and 5 without spines. Etymology. For the Tropic of Capricorn, which marks the species’ northern limit in Queensland, Australia. The name is a noun in apposition. Distribution. Australia, Queensland, 23°S – 27° 30' S; Fiji; French Polynesia. Remarks. Neaxius capricornicus and N. glyptocercus are immediately differentiated from N. acanthus in having a prominent supra-antennal spine on the anterior margin of the carapace, and both the cervical groove and second antenna article unarmed. Neaxius capricornicus differs from N. glyptocercus in having: 2–4 spines on the lower margin of the scaphocerite (vs. usually none, rarely 1 or 2 in N. glyptocercus), 3–5 spines along the distolateral ridge of the merus of the cheliped (vs. usually none, rarely one), 3–11 spines on the lower margin of the merus of pereopod 2 (vs. none), 8–12 (rarely fewer) spines on the lower margin of the merus of pereopod 3 (vs. none), one spine on the anterior margin of the branchiostegite (vs. 2 or 3) and the dorsalmost spine of the anterolateral carapace margin directed anterolaterally (vs. anteriorly). The two species were confused by Poore and Griffin (1979) who illustrated both in their fig. 8. Specimens from Fiji (ZMH K8392; Sakai, 2011: fig. 62A, E) and Tahiti (ZMH K41226; Sakai, fig. 62B) have 2 spines on the lower margin of the scaphocerite, 4 and 3 spines respectively along the distolateral ridge of peropod 1 merus, 4 and 10 spines respectively on the lower margin of pereopod 2, 8 and 10 spines respectively on the lower border of pereopod 3 merus and 1 spine on the anterior margin of the branchiostegite, within the range of the Australian material., Published as part of Poore, Gary C. B. & Dworschak, Peter C., 2018, The Indo-West Pacific species of Neaxiopsis and Neaxius (Crustacea: Axiidea: Strahlaxiidae), pp. 15-28 in Memoirs of Museum Victoria (Mem. Mus. Vic.) (Mem. Mus. Vic.) 77 on pages 21-24, DOI: 10.24199/j.mmv.2018.77.02, http://zenodo.org/record/8065257, {"references":["Poore, G. C. B., and Griffin, D. J. G. 1979. The Thalassinidea (Crustacea: Decapoda) of Australia. Records of the Australian Museum 32: 217 - 321. http: // dx. doi. org / 10.3853 / j. 0067 - 1975.32.1979.457","Tudge, C. C., and Cunningham, C. W. 2002. Molecular phylogeny of the mud lobsters and mud shrimps (Crustacea: Decapoda: Thalassinidea) using nuclear 18 s rDNA and mitochondrial 16 s rDNA. Invertebrate Systematics 16: 839 - 847. https: // doi. org / 10.1071 / IS 02012","Tsang, L. M., Lin, F. - J., Chu, K. H., and Chan, T. - Y. 2008. Phylogeny of Thalassinidea (Crustacea, Decapoda) inferred from three rDNA sequences: implications for morphological evolution and superfamily classification. Journal of Zoological Systematics & Evolutionary Research 46: 216 - 223. https: // doi. org /: 10.1111 / j. 1439 - 0469.2008.00459. x","Robles, R., Tudge, C. C., Dworschak, P. D., Poore, G. C. B., and Felder, D. L. 2009. Molecular phylogeny of the Thalassinidea based on nuclear and mitochondrial genes. Pp. 309 - 326 in: Martin, J. W., Crandall, K. A., and Felder, D. L. (eds), Crustacean Issues Vol. 18: Decapod Crustacean Phylogenetics. CRC Press: Bocan Raton. http: // dx. doi. org / 10.1201 / 9781420092592 - c 15","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616. https: // doi. org / 10.1163 / 9789047424185","Milne-Edwards, A. 1879. Additions a la famille des Thalassiens. Bulletin des Sciences, par la Societe Philomatique de Paris (ser. 7) 3: 110 - 115. https: // biodiversitylibrary. org / page / 31660160","Martens, E. von 1868. Uber einige neue Crustaceen. Monatsberichte der Koniglichen Preussischen Akademie der Wissenschaften zu Berlin 1868: 608 - 615. http: // biodiversitylibrary. org / page / 35990130"]}

Allaxiopsis Sakai, 2011 Allaxiopsis Sakai, 2011: 34–35. Remarks. Sakai (2011) included three species in Allaxiopsis but confused their records. The type species, Paraxius picteti Zehntner, 1894, was described from a single female (cl. 10 mm) collected at Ambon, Indonesia. Two males (the larger cl. 8.5 mm) were recorded from Siboga station 209 at Kabaena I., Indonesia, by De Man (1905) and then re-illustrated (De Man, 1925). More specimens were recorded from Guam, Marshall Islands, and Fiji by Kensley (2003). Allaxiopsis spinimana (De Man, 1905) was originally described as a variety of A. picteti from Siboga station 209 based on a 9.25 mm female and a smaller male. The variety was treated at the species level by Sakai and de Saint Laurent (1989) and has been rediscovered (see below). Allaxiopsis bougainvillensis Sakai, 2011 (type species of the genus) was described from much smaller specimens (4.5 mm and 4.9 mm) from Bougainville, Papua New Guinea and is treated here as a synonym of A. spinimana. Sakai included Kabaena I., Sulawesi, Indonesia, in the distribution of all three species and as type locality of the last two, contradicting the data provided with his type specimens. Each of the two species is diagnosed here with a minimal character suite., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on page 2, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616.","Zehntner, L. 1894. Voyage de M. M. Bedot et C. Pictet dans l'Archipel Malais. Crustaces de l'Archipel Malais. Revue Suisse de Zoologie 2: 135 - 214. http: // biodiversitylibrary. org / page / 9970404","Man, J. G. de 1905. Diagnoses of new species of macrurous decapod Crustacea from the \" Siboga-Expedition \". Tijdschrift der Nederlandsche Dierkundige Vereeniging 9: 587 - 614. http: // biodiversitylibrary. org / page / 9779712","Man, J. G. de 1925. The Decapoda of the Siboga-Expedition. Part VI. The Axiidae collected by the Siboga-Expedition. Siboga Expeditie Monographie 39 a 5: 1 - 127. http: // decapoda. nhm. org / pdfs / 15372 / 15372. pdf","Kensley, B. 2003. Axioid shrimps from Guam (Crustacea, Decapoda, Thalassinidea). Micronesica 35 - 36: 359 - 384. https: // repository. si. edu / handle / 10088 / 10970","Sakai, K., and de Saint Laurent, M. 1989. A check list of Axiidae (Decapoda, Crustacea, Thalassinidea, Anomula), with remarks and in addition descriptions of one new subfamily, eleven new genera and two new species. Naturalists, Publications of Tokushima Biological Laboratory, Shikoku University 3: 1 - 104."]}

Neaxiopsis Sakai and de Saint Laurent, 1989 Neaxiopsis Sakai and de Saint Laurent, 1989: 32.— Poore, 1994: 100.— Sakai, 2011: 320. Remarks. The genus is recognisable from the broad plate-like rostrum with an apical notch. Sakai (2011) provided a key to distinguish the two species but confused their synonymies., Published as part of Poore, Gary C. B. & Dworschak, Peter C., 2018, The Indo-West Pacific species of Neaxiopsis and Neaxius (Crustacea: Axiidea: Strahlaxiidae), pp. 15-28 in Memoirs of Museum Victoria (Mem. Mus. Vic.) (Mem. Mus. Vic.) 77 on page 15, DOI: 10.24199/j.mmv.2018.77.02, http://zenodo.org/record/8065257, {"references":["Sakai, K., and Saint Laurent, M. de 1989. A check list of Axiidae (Decapoda, Crustacea, Thalassinidea, Anomula), with remarks and in addition descriptions of one new subfamily, eleven new genera and two new species. Naturalists, Publications of Tokushima Biological Laboratory, Shikoku University 3: 1 - 104. https: // decapoda. nhm. org / pdfs / 12320 / 12320. pdf","Poore, G. C. B. 1994. A phylogeny of the families of Thalassinidea (Crustacea: Decapoda) with keys to the families and genera. Memoirs of the Museum of Victoria 54: 79 - 120. https: // doi. org / 10.24199 / j. mmv. 1994.54.03","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616. https: // doi. org / 10.1163 / 9789047424185"]}

Poore, Gary C. B. (2018): Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae). Memoirs of Museum Victoria 77: 1-14, DOI: 10.24199/j.mmv.2018.77.01, URL: http://dx.doi.org/10.24199/j.mmv.2018.77.01

Allaxiopsis spinimana (De Man, 1905) Fig. 5 Axiopsis Picteti var. spinimana De Man, 1905: 597. Axiopsis (Axiopsis) Picteti var. spinimana .— De Man, 1925: 6, 70, 96, pl. 7 fig. 17. Allaxius spinimanus.— Sakai and de Saint Laurent, 1989: 75. Allaxiopsis spinimana.— Sakai, 2011: 40. Allaxiopsis bougainvillensis Sakai, 2011: 37–39, fig. 3. Syn. nov. Material examined. Papua New Guinea. Bougainville, Teop I., 05° 34.3' S, 155° 4.7' E, (as ‘ Tiop Bougainville, German New Guinea’, H. Schoede, ZMB 14440 (holotype female, 4.9 mm; paratype female, 4.5 mm of Allaxiopsis bougainvillensis Sakai, 2011) (both photographed by C.O. Coleman). Madang Province, Channel between Pik I. and Kranket I., 05° 09.6' S, 145° 49.7' E, 3–8 m, coll. R. Hanley, NMV J67992 (2 ovigerous females, 7.5, 7.8 mm; 3 males, 3.2–5.0 mm; part of larger collection, NTMAG Cr.0100212). Type locality. Indonesia, off south point of Kabaena I., 22 m (Siboga stn 209). Diagnosis. Major cheliped, propodus with blunt tubercles on proximal lateral face, more prominent nearer upper margin becoming spine-like and more hooked towards distal upper margin. Minor cheliped, propodus with few tubercles on proximal lateral face, upper margin with 3 spines. Supplementary description. Rostrum acute, depressed, 0.3 length of rostral base–cervical groove, with pair of erect lateral spines near apex, larger pair at midpoint, and ventral tubercle. Gastric carina difficult to differentiate; median gastric carina obsolete except near base of rostrum, with sequence of 1, 1, 2 teeth; submedian gastric carina obsolete, with 1 tooth anteriorly and 2 or 3 teeth posteriorly; supraocular spine oblique, not marginal; lateral gastric carina, with 2 blunt teeth. Eyestalk reaching beyond end of rostrum. Antenna article 2 with small distal spine; scaphocerite 4 times as long as greatest height (lateral view), reaching sixth length of article 4. Major cheliped ischium, merus and carpus each smooth on lower margin; propodus swollen, lateral face tuberculate over proximal half, tubercles larger closer to upper margin, upper margin about equal to greatest height, with 2 rows each of 6 spines, the larger ones sharper and more hooked distally; fixed finger 0.45 times length of upper margin of propodus, with 2 blunt distal teeth along cutting edge, with short tuberculate mesial ridge; dactylus 2.1 times as long as wide, with lateral carina near upper margin, cutting edge with 2 low rounded teeth in proximal half. Minor cheliped as long as major cheliped, propodus about 0.5 times as high as on major cheliped; ischium and merus smooth on lower margin; propodus swollen, propodus upper margin 1.5 times greatest height, lateral face with 3 tubercles on proximal lateral face, upper margin with 3 teeth, second and third sharp; fixed finger almost as long as upper margin of propodus, with 2 distal teeth on cutting edge; dactylus 4 times as long as wide, cutting edge smooth. Telson 1.4 times as wide as long at level of most anterior lateral teeth; distal margin 0.8 times telson greatest width; lateral margin with 3 teeth; distal margin excavate, with 1 lateral articulating robust seta, lateral fixed spine, with median spine; face with 2 pairs of spines. Male pleopod 2 appendix masculina 1,3 times as long as appendix interna, stiff setae on posterior face. Uropodal endopod 1.8 times as long as wide; anterior margin strong lobed proximally (as rounded shoulder), otherwise concave with spine at midpoint, with subdistal and distal spine; posterior distal margin curved, with 10 spines, the most distal 2 submarginal, anterodistal angle marked by 2 spines; facial rib with 3 spines. Uropodal exopod semicircular, 1.8 times as long as wide; anterior margin of article 1 convex, with 6 marginal teeth; posterior margin straight, with 5 distal spines set obliquely; distal margin transverse, 2 marginal spines, strong articulating spine near anterior corner, facial rib with 3 spines; article 2 with 5 teeth along distal margin. Colour. Traces of purple on pereopod 1 propodus and dactylus on preserved material. De Man (1925) described the colour as being similar to A. picteti but more violet in parts. Juveniles and adults of A. picteti appear to differ so this species may also differ. Distribution. Indonesia, S Sulawesi; Papua New Guinea, Central Province, Bougainville; shallow heights. Remarks. De Man (1905) based Axiopsis picteti var. spinimana on two syntypes from the ‘Anchorage off the south point of Kabaena-island’, Indonesia (Siboga stn 209), the same locality at which he also recorded A. picteti. De Man (1925) described his two syntypes in moderate detail but illustrated only the distinctive cheliped. Allaxiopsis bougainvillensis Sakai, 2011, is based on two female specimens (ZMB 14440) from Papua New Guinea, which Sakai referred to as the holotype with both chelipeds (‘lectotype’ in fig. 3 caption) and a paratype without chelipeds. They are correctly identified on the ZMB label as ‘ Axiopsis (Axiopsis) picteti var. spinimana De Man, 1905 ’, possibly by H. Schoede. In describing his new taxon, Sakai (2011) correctly stated that these specimens are not types but used this observation to justify a new species without stating how it differed from A. (A.) picteti spinimana. He did not illustrate or describe the distinctive spinose chelipeds of the holotype (photographs of which were provided to me by C.O. Coleman), which are clearly identical to those in De Man’s (1925) figure of A. spinimana and to those figured here from other material. The supposed differences in gastric sculpture between A. bougainvillensis and A. picteti are small and not relevant. The type locality of A. bougainvillensis was given by Sakai (2011) as ‘ Triop Bougainville, German New Guinea’, a mistranscription of Tiop written on the label, which is now spelled Teop. The species shares the trifid rostrum, regular pattern of blunt gastric spines, short scaphocerite, broad telson, uropodal endopod with shouldered anterior margin, and spinose uropodal rami with A. picteti. The most significant difference is the presence of chelipeds with spinose palms, the distal spines on the upper margin of the palm having a characteristic hooked form, characters that formed the basis of the identification of the Papua New Guinea specimens. Most of the characters of Sakai’s (2011) diagnosis of this species are of generic value only., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on pages 6-8, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Man, J. G. de 1905. Diagnoses of new species of macrurous decapod Crustacea from the \" Siboga-Expedition \". Tijdschrift der Nederlandsche Dierkundige Vereeniging 9: 587 - 614. http: // biodiversitylibrary. org / page / 9779712","Man, J. G. de 1925. The Decapoda of the Siboga-Expedition. Part VI. The Axiidae collected by the Siboga-Expedition. Siboga Expeditie Monographie 39 a 5: 1 - 127. http: // decapoda. nhm. org / pdfs / 15372 / 15372. pdf","Sakai, K., and de Saint Laurent, M. 1989. A check list of Axiidae (Decapoda, Crustacea, Thalassinidea, Anomula), with remarks and in addition descriptions of one new subfamily, eleven new genera and two new species. Naturalists, Publications of Tokushima Biological Laboratory, Shikoku University 3: 1 - 104.","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616."]}

Paraxiopsis austrinus (Sakai, 1994) Eutrichocheles austrinus Sakai, 1994: 185, figs. 6, 7.— Sakai 2011: 111. Paraxiopsis austrinus.— Kensley 2003, 373.— Poore and Collins 2009: 266, fig. 29. Material examined. Papua New Guinea. New Ireland Province, Kavieng region, KAVIENG 2014 stations. Mouth of Albatross Passage, E side, 02° 35.2' S, 150° 43.1' E, 13 m (stn KB72), IU-2014- 1046 (male, 6.1 mm). S coast of Baudison I., 02° 45.2' S, 150° 41.7' E, 22–27 m (stn KB68), IU-2014-1153 (male, 7.6 mm; ovigerous female, 6.3 mm). E of Albatross Passage, 02° 45.2' S, 150° 43.4' E, 13–17 m (stn KB24), IU-2014-2364 (male, 9.0 mm). Diagnosis. Carapace smooth, with tomentum of short and longer setae. Rostrum with 0–3 small lateral teeth; lateral gastric carina with supraorbital spine plus 2 teeth; submedian gastric carina with 6–8 teeth; median gastric carina without spines. Telson with 3 or 4 pairs of dorsal spines. Cheliped merus with 2 spines on upper margin, palm unornamented. Male pleopod 1 absent in small specimens, single article in adults. Distribution. Northern Australia; New Ireland Province, Papua New Guinea; to 27 m depth. Remarks. The new material extends the range of this species from Darwin, northern Australia, to Papua New Guinea. The species differs from the original description only in having no rostral spines (three small spines in Australian specimens) and in having one (rather than two) post-supraocular spine on the lateral gastric carina. All of the males lack pleopod 1 but possess a minute tubercle in its place. Kensley (2003) and Poore and Collins (2009) justified the generic placement of this species., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on page 11, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Sakai, K. 1994. Eleven species of Australian Axiidae (Crustacea: Decapoda: Thalassinidea) with descriptions of one new genus and five new species. The Beagle, Occasional Papers of the Northern Territory Museum of Arts and Sciences 11: 175 - 202. http: // hdl. handle. net / 10070 / 256995","Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616.","Kensley, B. 2003. Axioid shrimps from Guam (Crustacea, Decapoda, Thalassinidea). Micronesica 35 - 36: 359 - 384. https: // repository. si. edu / handle / 10088 / 10970","Poore, G. C. B., and Collins, D. J. 2009. Australian Axiidae (Crustacea: Decapoda: Axiidea). Memoirs of Museum Victoria 66: 221 - 287. http: // doi. org / 10.24199 / j. mmv. 2009.66.20"]}

Ralumcaris Sakai, 2011 Ralumcaris Sakai, 2011: 182–183., Published as part of Poore, Gary C. B., 2018, Burrowing lobsters mostly from shallow coastal environments in Papua New Guinea (Crustacea: Axiidea: Axiidae, Micheleidae), pp. 1-14 in Memoirs of Museum Victoria 77 on page 11, DOI: 10.24199/j.mmv.2018.77.01, http://zenodo.org/record/8065241, {"references":["Sakai, K. 2011. Axioidea of the world and a reconsideration of the Callianassoidea (Decapoda, Thalassinidea, Callianassida). Crustaceana Monographs 13: 1 - 616."]}