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Deep-sea ophiuroids from western Mexico have been documented since 1899, but mostly by non-Mexican expeditions. TALUD is a Mexican project designed to study the deep-sea fauna from Mexico. As part of it, the present contribution provides for the first time detailed information about the taxonomy and distribution, as well as images, of deep-sea ophiuroids from western Mexico, representing a useful taxonomic identification tool for Ophiuroidea from the eastern Pacific. A total of 38 species of ophiuroid (35 identified at species level, one at genus level, and two as confer) were collected from 83 stations located at 123‒2,309 m depth. At a regional scale, several new species records are presented: six for western Baja California, five for western Baja California Sur, two for the Gulf of California, four for Jalisco, 14 for Colima, and five for Guerrero. Geographic (six) and bathymetric (seven) distribution ranges of species are extended. An updated list of deep-sea ophiuroids (61 species) from western Mexico is provided together with an identification key to species collected during this survey. In addition, nine records of deep-sea ophiuroids for the Mexican Pacific are unproven, doubtful or invalid. We corroborated the presence of Ophiacantha eurypoma and Ophiacantha pacifica in the study area and added Amphiura gymnogastra as the first record for Mexico. We propose to transfer Ophiacantha phragma to Ophiolimna on account of it having both granules and spines on the dorsal disc and striated arm plates. TALUD cruises collected 57 % of the total deep-sea species known to occur off Mexico, making it the most important survey of deep-sea Ophiuroidea carried out in western Mexico to date.

Asteronyx loveni Müller & Troschel, 1842 Figs 2, 3A–B, 4A, D–E Asteronyx loveni Müller & Troschel, 1842: 119, pl. X figs 3–5. Ophiuropsis lymani Studer, 1884: 55, pl. V figs 12a–d. Asteronyx locardi Koehler, 1895: 470–471, fig. 10 Asteronyx loveni – Clark 1923: 314–315. — Mortensen 1927: 158–160, fig. 90 — Paterson, 1985: 13–15, fig. 15. Asteronyx locardi – Koehler 1896: 88–89, pl. 3 fig. 25. Material examined MAURITANIA • 1 spec., 25.22 mm dd; 19°34′14′′– 19°31′34′′ N, 17°31′44′′– 17°30′21′′ W; depth 1689– 1628 m; 23 Nov. 2007; Maurit-1107 exped.; stn MU22; Maurit-1107-04528; LZM-UV • 12 specs, 6.08–21.71 mm dd; 19°25′29″– 19°22′44″ N, 17°33′17″– 17°32′11″ W; depth 1778–1811 m; 26 Nov. 2007; Maurit-1107 exped.; stn MU31; Maurit-1107-05231; LZM-UV • 10 specs, 6.83–19.28 mm dd; 19°55′41″– 19°53′05″ N, 18°01′07″– 18°02′01″ W; depth 1808–1862 m; 21 Nov. 2008; Maurit-0811 exped.;stn MU92; Maurit-0811-03931; LZM-UV • 4 specs, 64.90– 22.98 mm dd; 19°51′02″– 19°49′33″ N, 17°55′33″– 17°53′00″ W; depth 1740–1769 m; 21 Nov. 2008; Maurit-0811 exped.; stn MU93; Maurit-0811-03725; LZM-UV • 2 specs, 9.60–12.56 mm dd; 19°35′15″– 19°32′43″ N, 17°35′13″– 17°33′37″ W; depth 1720–1734 m; 21 Nov. 2008; Maurit-0811 exped.; stn MU94; Maurit-0811-03928; LZM-UV • 1 spec., 11.07 mm dd; 19°59′28″– 19°59′01″ N, 17°57′28″– 17°59′07″ W; depth 1746–1749 m; 22 Nov. 2009; Maurit-0911 exped.; stn MU193; Maurit-0911-03154; LZM-UV • 1 spec., 25.74 mm dd; 16°08′44″– 16°11′14″ N, 17°10′08″– 17°08′40″ W; depth 1595 m; 6 Dec. 2010; Maurit-1011 exped.; stn MU274; Maurit-1011-02982; LZM-UV. WESTERN SAHARA • 1 spec., 11.01 mm dd; 21°33′13″– 21°36′08″ N, 18°07′26″– 18°07′09″ W; depth 1860– 1820 m; 17 Nov. 2006; Maroc-0611 exped.; stn MO198; Maroc-0611-16135; LZM-UV • 1 spec., 5.81 mm dd; 22°59′13″– 22°56′19″ N, 17°37′30″– 17°38′12″ W; depth 1562–1577 m; 26 Nov. 2006; Maroc-0611 exped.; stn MO230; Maroc-0611-16155; LZM-UV. GUINEA BISSAU • 2 specs, 13.24–18.81 mm dd; 10°01′18″– 10°00′24″ N, 17°24′56″– 17°25′05″ W; depth 902–908 m; 29 Oct. 2008; Bissau-0810 exp.; stn BS166; Bissau-0811-06529; LZM-UV. Distribution Asteronyx loveni Müller & Troschel, 1842 is a circumglobal species, widely distributed across the three major oceans (Indian, Pacific and Atlantic). In the Atlantic Ocean, it has been recorded on both sides: in the West Atlantic, from North USA to West Indies (Hernández-Herrejón et al. 2008), and in the East Atlantic, from Norway (Döderlein 1911) to South Africa (Mortensen 1933). It also has a wide bathymetric distribution, ranging from 100 to 4721 m (Smirnov et al. 2014). We collected the species at eleven stations from Western Sahara, Mauritania and Guinea-Bissau waters, between 902 and 1862 m. Remarks This is a deep-sea-water species generally associated with gorgonians and pennatularians (Mortensen 1927). Our specimens were always associated with pennatularians Distichoptilum gracile Verrill, 1882 and Anthoptilum murrayi Kölliker, 1880. Living colour of the species is cream or pinkish orange, more intense in the central part of the disc. The innermost arm spine much larger than the other spines and a hooked arm spine at the tip of the arm are the most distinctive characteristic for this species., Published as part of Calero, Belén & Ramil, Fran, 2023, Euryalida (Echinodermata, Ophiuroidea) from Northwest Africa, pp. 46-75 in European Journal of Taxonomy 870 on pages 51-53, DOI: 10.5852/ejt.2023.870.2117, http://zenodo.org/record/7938618, {"references":["Muller J. & Troschel F. H. 1842. System der Asteriden. F. Vieweg und Sohn, Braunschweig. https: // doi. org / 10.5962 / bhl. title. 11715","Studer T. 1884. Verzeichnis der wahrend der Reise S. M. S. \" Gazelle \" um die Erde, 1874 - 76 gesammelten Asteriden und Euryaliden. Abhandlungen der Preussischen Akademie der Wissenschaften: 1 - 64.","Koehler R. 1895. Draguage profonds executes a bord du ' Caudan' dans le Golfe de Gascogne. Rapport preliminaire sur les Echinodermes. Revue Biologique du Nord de la France VII: 439 - 506.","Clark H. L. 1923. The Echinoderm fauna of South Africa. Annals of The South African Museum XIII: 221 - 432.","Mortensen Th. 1927. Handbook of the Echinoderms of the British Isles. Oxford University Press, Rotterdam. https: // doi. org / 10.5962 / bhl. title. 6841","Paterson G. L. J. 1985. The deep-sea Ophiuroidea of the North Atlantic Ocean. Bulletin of the British Museum (Natural History) 49 (1): 1 - 162.","Koehler R. 1896. Resultats scientifiques de la campagne du Caudan dans le Golfe de Gascogne. Echinodermes. Annales de l'Universite de Lyon 26: 33 - 122. https: // doi. org / 10.5962 / bhl. title. 65730","Hernandez-Herrejon L. A., Solis-Marin F. A. & Laguarda-Figueras A. 2008. Ofiuroideos (Echinodermata: Ophiuroidea) de las aguas mexicanas del golfo de Mexico. Revista De Biologia Tropical 56 (3): 83 - 167.","Doderlein L. 1911. Uber japanische und andere Euryalae. KB Akademie der Wissenschaften, Munich. https: // doi. org / 10.5962 / bhl. title. 16334","Mortensen Th. 1933. Papers from Dr. Th. Mortensen's Pacific Expedition 1914 - 16. LXV. Echinoderms of South Africa (Asteroidea and Ophiuroidea). Videnskabelige Meddelelser fra Dansk naturhistorisk Forening i Kobenhavn: 93: 215 - 400.","Smirnov I. S., Piepenburg D., Ahearn C. & Juterzenka K. V. 2014. Deep-sea fauna of European seas: An annotated species check-list of benthic invertebrates living deeper than 2000 m in the seas bordering Europe. Ophiuroidea. Invertebrate Zoology 11 (1): 192 - 209."]}

From 2004 to 2012, ten multidisciplinary oceanographic surveys were conducted along the coast of Northwest Africa, between the Strait of Gibraltar and the northern border of Sierra Leone. A total of five species of Euryalida Lamarck, 1816 belonging to three families were captured at 29 of the 1298 stations sampled in the area. Among them, Astrodendrum juancarlosi sp. nov. is described and figured in this paper. Ophiocreas oedipus Lyman, 1879 is recorded for the first time on West African continental margin and Gorgonocephalus pustulatum (H.L. Clark, 1916), an Indo-Pacific species only known from South African coast in the Atlantic, is reported off Guinea-Bissau, greatly extending to the North its Atlantic distribution. In addition, Asteroschema inornatum Koehler, 1906, a northeast Atlantic species, is recorded for the first time in African waters, off Western Sahara, extending its range of distribution to the south. Our data also extend the bathymetric distribution of A. inornatum to shallower waters and of G. pustulatum to deeper waters. The association of some euryalids with certain species of pennatulaceans and gorgonians is also described.

Astrodendrum juancarlosi sp. nov. urn:lsid:zoobank.org:act: ECD0622E-6FAF-4C72-B102-F1B94D8ECBFB Figs 3E–F, 7–9 Diagnosis Species with small granule-like external ossicles, ending in a crystalline point, covering the dorsal and lateral interradial areas of the disc. Ventral disc areas and arms covered by domed granule-like external ossicles without any crystalline point. Two or three terminal projections on each arm spine; one secondary teeth on each valve. Etymology The specific epithet ‘ juancarlosi ’ was chosen as a tribute to Mr Juan Carlos Calero, father of the first author. Material examined Holotype GUINEA BISSAU • 2 specs, 40.43–56.81 mm dd; 10°18′55″ N, 16°25′07″ W; depth 79 m; 4 Nov. 2008; Bissau-0810 exped.; stn BS200; Bissau-0810-06403; MNCN 29.02/1534. Paratypes GUINEA BISSAU • 2 specs, 28.20–51.16 mm dd; 11°08′07″– 11°09′33″ N, 17°15′20″– 17°15′44″ W; depth 109 m; 29 Oct. 2011; CCLME-1110 exped.; CCLME-1110 exped.; stn BT53; MHN USC-10132 -1 and 2 • 1 spec., 40.43 mm dd; 10°18′55″ N, 16°25′07″ W; depth 79 m; 4 Nov. 2008; Bissau-0810 exped.; Bissau-0810 exped.; stn BS200; MNCN 29.02/1535. WESTERN SAHARA • 1 spec., 44.62 mm dd; 26°26′23″– 26°25′06″ N, 14°25′30″– 14°26′23″ W; depth 67– 58 m; 29 Nov. 2011; CCLME-1110 exped.; CCLME-1110 exped.; stn BT215; CFM-IEOMA-7776. • 1 spec., 46.70 mm dd; 14°57′00″– 14°58′09″ N, 17°39′08″– 17°38′13″ W; depth 797 m; 25 May 2012; CCLME-1205 exped.; CCLME-1205 exped.; stn BT368; CCLME-1205-03248; LZM-UV. Additional material GUINEA BISSAU • 1 spec., 10.07 mm dd; 11°05′09″– 17°03′15″ N, 11°04′15″– 17°03′10″ W; depth 46–47 m; 26 Oct. 2008; Bissau-0810 exped.; stn BS151; Bissau-0810-06146; LZM-UV. Description (holotype) DISC. Five-lobed in shape, slightly excavated inter-radially (Fig. 8A), with no peripheral calcareous plates on rim. Radial shields tumid, long (almost raising the centre of disc) and narrow, which is deeply sunken (Fig. 8C). Radial shields completely concealed by external ossicles, bar-shaped, as wide proximally as distally, but more separated distally, converging towards centre of disc. Distally, radial shields end on enlarged, slightly concave and oval-shaped plate covered by minute granules (Fig. 8C–D). Dorsal disc covered by small granule-like external ossicles (Fig. 8A, C–D), each one ending in terminal crystalline point. At edge of disc, ossicles more densely packed and without crystalline point (Fig. 8C), and bigger in size between radial shields (Fig. 8C–D). Ossicles concealing radial shields similar to those from dorsal disc but more densely packed.Ventral inter-radial areas densely covered by mosaic of small irregular flat plates with granule-like external ossicles without terminal point. Oral shield, adoral shield, oral plates, along edge of mouth frame and ventral arm plates more densely covered by similar external ossicles. Mouth frame sunken (Fig. 8E). Interradial surface of lateral disc covered by external ossicles similar but smaller than those covering dorsal disc. Two large genital slits on each interradius running almost vertically along first five or six brachial segments after first fork (Fig. 8F). Conical external ossicles with terminal crystalline point more developed on adradial edge of genital slits. One oval-shaped and well-developed madreporite located just outside mouth frame (Fig. 8E). Both, tooth and oral papillae spiniform, especially larger apical ones. Mouth and infradental papillae form continuous series along mouth frame (Fig. 8E). Teeth varying in position and size, being irregular in outline and more or less irregularly disposed. ARMS. Arms branching, with first fork before disc margin and second one located at margin. Nevertheless, in smaller specimens (juvenile), first fork located on margin of disc. Arms tapering gradually towards tips, completely covered, both, dorsally and ventrally, by domed granule-like external ossicles (Fig. 9A); these granules somewhat bigger than disc ones and without any crystalline point. Dorsal side of arms carry pedicellarial bands along whole arms. Valves with one secondary tooth downwardly curved (Fig. 9C). Some sunken transverse furrow between segments, giving arms an annulated appearance. Indication observed of median furrow along arm (Fig. 8G). Ventral side of arms with noticeable transverse naked furrows between segments until second fork; afterwards, furrows become smaller, disappearing after third fork. First two pores without arm spine. Arm spines beginning at third pair of pores with only one small spine at third and fourth pair of pores, two arm spines (sometimes one) afterwards and three arm spines (sometimes two) after second fork. Arm spines short and wide, ending in two or three hyaline points (Fig. 9F). Vertebrae streptospondylous (Fig. 9G–K). COLOUR. Living specimens showing varying colours, from creamish-pink to dark orange and brown to gray (Fig. 3E–F) with clear ventral part; preserved specimens are white. OSSICLE MORPHOLOGY. External ossicles on dorsal surface of disc, including radial shields, are granule-shaped and ending in a crystalline point (Fig. 9A). Baseplates oval-shaped with three to five tubercleshaped articulations for pedicellarial (Fig. 9D). External ossicles on baseplates granule-like shaped, approximately 200 µm in length and 100 µm in height (Fig. 9B). Valves with single inner tooth downwardly directed, and reticular structure (Fig. 9C). Lateral arm plates long, bar-like, with tuberculous stereom, spines placed in external lobe of plate (Fig. 9E). Arm spines ovoid-shaped with two or three small projections, not transforming into hook-shaped spines on distal portion (Fig. 9F). Vertebrae with hourglass-shaped streptospondylous articulations (Fig. 9G–K). Branching vertebra wider and with two surfaces for articulation. Distribution This species has been recorded in the Northwest African coast, from the Western Sahara to Guinea-Bissau waters. Its bathymetric distribution ranges between 47 and 797 m. Remarks The genus Astrodendrum was established by Döderlein (1911) for Gornocephalus sagaminus Döderlein, 1902. He realised that all species that belong to Gorgonocephalus Leach 1815 are characterised by the presence of a well-developed belt of calcareous plates at the margins of the disc. However, species of Astrodendrum have no ring of calcareous plates at the rim. Additionally, the arm spines appear before the first fork, as in Gorgonocephalus; however, in Astrodendrum Döderlein, 1911, these arm spines are much smaller, hardly reaching ⅓ of the segment length, and their number is reduced: with three (or rarely four) on each side. Taxonomic studies dealing with this genus are scarce, and we have only found a revision of the genus recently published by Okanishi & Fujita (2018). According to these authors, the genus is characterised by having five branching arms, with less than six segments before the first fork; lack of calcareous plates on the edge of the disc margin; variously shaped external ossicles or no ossicles on the disc; a madreporite placed on the innermost part of the interradial lateral disc; and valves from the dorsal arms with one secondary tooth. Currently, only six species have been assigned to this genus. Among them, only Astrodendrum capense (Mortensen, 1933), described from Durban, South Africa (Mortensen 1933; Clark & Courtman-Stock 1976), has been found in the Atlantic Ocean – Namibia (Alva & Vadon 1989). Astrodendrum elingamita Baker, 1974 has been reported in New Zealand and Philippines (Baker 1974; Okanishi & Fujita 2018); Astrodendrum galapagense A.H. Clark, 1916 from Galapagos Islands; Astrodendrum laevigatum (Koehler, 1897) from Colombo (Sri Lanka); and Astrodendrum sagaminum (Döderlein, 1902) from Japan, East China Sea and Sri Lanka (Döderlein 1902, 1911; Clark 1911; Bomford 1913; Matsumoto 1917; Irimura & Kubodera 1998); and the recently described Astrodendrum spinulosum Okanashi & Fujita, 2018 also from Japan. In addition to the shape, size and arrangement of external ossicles – widely used as an important specific taxonomic character (Baker 1974, 1980; McKnight 2000) – Okanishi and Fujita (2018) included the possibility of the lack of external ossicles (as in the case of A. laevigatum), and they also proposed three new taxonomic characters to distinguish species of Astrodendrum: • absence/ presence of bulges on lateral ridges of proximal portion of arm • number of terminal projections of arm spines on proximal portion of arm • number of secondary teeth of hook-shaped arm spines on distal portion of the arm The main morphological features of all known species of Astrodendrum, including A. juancarlosi sp. nov., are summarized in Table 2. Astrodendrum spinulosum differs from the rest of species by the presence of bulges on lateral ridges of proximal portion of the arm. The new species here described, also differs from A. spinulosum by the number of terminal projections of arm spines on the proximal portion of the arm (three in the case of the new species and one in A. spinulosum). In addition, A. spinulosun has cone-shaped external ossicles, while A. juancarlosi sp. nov. has granule like ossicles ending in a crystalline point at the dorsal surface of the disc. Astrodendrum juancarlosi sp. nov. is more similar to A. elingamita in the shape of the ventral coverage and the lack of a scale in the first tentacle pore. Nevertheless, A. elingamita has the first fork in the margin of the disc, while it is located before the margin in our species. The polygonal plates of the ventral covering are closer in the A. elingamita than in our specimen. Our specimens also differ from A. elingamita by having one type of dome-shaped granules with 1–2 hyaline terminal points rather than two smooth types. Astrodendrum sagaminum differs from Astrodendrum juancarlosi sp. nov. in also having two types of granules and naked arms and ventral disk. Astrodendrum capense has several medium-sized conical tubercles along the radial shields; it also has some smaller conical tubercles along the inter-radial disc margin, both ending in small thorns. Moreover, the disc is closely covered with minute and smooth plates. Astrodendrum galapagense has a dorsal coarse armament on the disc and arms. The external ossicles on the aboral disc are plate-shaped at periphery and conical at center, both slightly in contact, while on the oral surface has a few small widely scattered granules, except in the ventral interbrachial areas. Astrodendrum laevigatum is covered by a thin, transparent, soft and perfectly smooth tegument without any granules or spines. According to the description of this species in the literature, there are some doubts about the inclusion of this species in the genus Astrodendrum. We consider necessary to review the type material before we can reach a conclusion on this issue. Therefore, in this paper we follow Okanishi & Fujita (2018) and keep the species within the genus Astrodendrum. Finally, our specimen has marked rectangular furrows that are absent in the rest of the species of Astrodendrum. Even though Mortensen (1933) described the underside of the arms of A. capense as flat and without any grooves, he pointed out that this “may be an indication of a transverse furrow between the segments from the first forking onwards” (Mortensen 1933: 286). See Table 2 for comparison of main morphological characteristics among species., Published as part of Calero, Belén & Ramil, Fran, 2023, Euryalida (Echinodermata, Ophiuroidea) from Northwest Africa, pp. 46-75 in European Journal of Taxonomy 870 on pages 59-67, DOI: 10.5852/ejt.2023.870.2117, http://zenodo.org/record/7938618, {"references":["Doderlein L. 1911. Uber japanische und andere Euryalae. KB Akademie der Wissenschaften, Munich. https: // doi. org / 10.5962 / bhl. title. 16334","Doderlein L. 1902. Japanische Euryaliden. Zoologischer Anzeiger 25 (659 - 684): 320 - 326.","Okanishi M. & Fujita T. 2018. A taxonomic review of the genus Astrodendrum (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) with description of a new species from Japan. Zootaxa 4392 (2): 289 - 310. https: // doi. org / 10.11646 / zootaxa. 4392.2.4","Mortensen Th. 1933. Papers from Dr. Th. Mortensen's Pacific Expedition 1914 - 16. LXV. Echinoderms of South Africa (Asteroidea and Ophiuroidea). Videnskabelige Meddelelser fra Dansk naturhistorisk Forening i Kobenhavn: 93: 215 - 400.","Clark A. M. & Courtman-Stock J. 1976. The Echinoderms of Southern Africa. Trustees of the British Museum (Natural History), London.","Alva V. & Vadon C. 1989. Ophiuroids from the western coast of Africa (Namibia and Guinea-Bissau). Scientia Marina 53 (4): 827 - 845.","Baker A. N. 1974. New species of brittle-stars from New Zealand (Echinodermata: Ophiiuroidea). Records of the Dominion Museum 8 (15): 247 - 266.","Clark H. L. 1916. Report on the Sea-Lilies, Starfishes, Brittle-Stars and Sea-Urchins obtained by the F. I. S. ' Endeavour' on the coast of Queensland, New South Wales, Tasmania, Victoria, South Australia, and Western Australia. Biological results of the fishing experiments carried on by the \" Endeavour \" 4 (1). Minister for Trade and Customs, Sydney. hhtps: // doi. org / 10.5962 / bhl. title. 13854","Clark H. L. 1911. North Pacific ophiurans in the collection of the United States National Museum. Bulletin of the United States National Museum (75): 1 - 302. https: // doi. org / 10.5479 / si. 03629236.75.1","Bomford T. L. 1913. A note on certain ophiiuroids in the Indian Museum. Records of the Indian Museum 9 (4): 219 - 225.","Matsumoto H. 1917. A monograph of Japanese Ophiuroidea, arranged according to a new classification. Journal of the College of Science, Imperial University, Tokyo, Japan XXXVIII (2): 1 - 407.","Irimura S. & Kubodera T. 1998. Ophiuroidea in the East China Sea. Memoirs of the National Science Museum, Tokyo 31: 135 - 143.","Baker A. N. 1980. Euryalinid Ophiuroidea (echinodermata) from Australia, New- Zealand, and the Southwest Pacific-Ocean. New Zealand Journal of Zoology 7 (1): 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","McKnight D. G. 2000. The marine fauna of New Zealand: Basket-stars and Snake-stars (Echinodermata: Ophiuroidea: Euryalinida). National Institute of Water and Atmospheric Research, Wellington, New Zealand."]}

Asteronyx longifissus Döderlein, 1927 Fig. 1A‒F Asteronyx longifissus Döderlein, 1927: 65‒68, pl. 7, figs. 1‒3.— A.M. Clark 1965: 68.— Hendler 1996: 123‒125, fig 7.2; 2018: 194‒198, fig. 1. Material examined. 164 individuals at five stations. TALUD VIII, Sta. 11, 2 ind. (ICML-EMU-11108); Sta. 20, 1 ind. (ICML-EMU-11095). TALUD XV, Sta. 20, 159 ind. (ICML-EMU-11098); Sta. 23, 1 ind. (ICML-EMU-11109); Sta. 24, 1 ind. (ICML-EMU-11699). Comparative material. Syntypes, 324 ind.: USNM E4061, USNM E4067, USNM E4069, USNM E4076, USNM E4081, USNM E4096, USNM E4109, USNM E4112, USNM E4117, USNM E4118, USNM E4120, USNM E4121, USNM E4242, USNM E4246 (Supplementary file 2). Description (ICML-EMU-11699). DD = 16 mm. Disc pentagonal, flat, indented interradially. Dorsal disc with thickened skin, lacking scales. RS multilayered, very prominent distally, almost reaching the center of the disc (Fig. 1A). Ventral interradii entirely covered by integument with some granule-shaped epidermal ossicles proximally. Genital slits oval, restricted to middle-distal part, elongate, covering approximately 3/4 of the interradius (Fig. 1B). OSh broader than long, rounded triangular. Madreporite not evident. AdSh broader than long, rectangular with rounded edges, separated by integument. Jaws bearing 8‒9 papillae at each side; OPa 4‒5, spiniform, elongated, separated; TPa four at jaw tips, spiniform, larger than OPa, separated. Teeth several, similar to TPa (Fig. 1C). Arms entirely covered by integument, coiled, gradually narrowing distally (Fig. 1D). LAP located on the ventral lateral side of vertebrae, short and rounded, prominent (Fig. 1E). First and second tentacle pores outside the mouth lacking ArSp; third to eight pores with one ArSp with serrated tip; subsequent pores with 2‒3 ArSp, hook-shaped, serrated, gradually reaching up to six in the middle of the arm; distal tentacle pores with four ArSp, ventralmost ArSp elongated. TSc lacking (Fig. 1E). Color pattern yellowish-brown (ethanol preservation) (Fig. 1A‒F). Habitat and distribution. From Oregon, USA, to Northern Mexico; 265‒ 1,800 m depth (Döderlein 1927; Maluf 1988; see Remarks). Associated with sea pens (Duffy et al. 2014). The material examined was collected off western Baja California Sur and in the southern Gulf of California; 530‒ 1,150 m depth. Remarks. Examination of the TALUD specimens and the type material of this species demonstrated that the oral shields can be partially or completely concealed or can be completely visible. Moreover, some specimens can have radial shields almost reaching the center of the disc or cover 3/4 of the diameter of the disc; this could be an artifact caused by preservation because of potential contraction of the soft disc, thus modifying the appearance of the radial shield coverage (pers. comm. Sabine Stöhr, 2022). Asteronyx longifissus has been previously recorded in Mexico only for western Baja California Sur and Guerrero (Honey-Escandón et al. 2008). Material from Guerrero is deposited at ICML-UNAM (ICML-UNAM 3.140.2, Isla de Ixtapa) and was examined. Morphological differences such as radial shields not multilayered, minute spines in the dorsal disc, and OPa not granule-like were observed. We conclude that the material from Guerrero does not correspond to A. longifissus but probably to a species new to science, and this record should be considered invalid. The discovery of A. longifissus during the Gulf of California cruises is a first for this area. This species is now known to range as far north as 25º56′N. Due to its northern affinity and the invalidation of the record in Guerrero, we suggest that A. longifissus distribution is probably limited to temperate waters in the northern American Pacific., Published as part of Granja-Fernández, Rebeca, Hendrickx, Michel E., Rangel-Solís, Pedro Diego & López-Pérez, Andrés, 2023, Deep-sea Ophiuroidea (Echinodermata) collected during the TALUD cruises in western Mexico, pp. 1-71 in Zootaxa 5259 (1) on page 13, DOI: 10.11646/zootaxa.5259.1.1, http://zenodo.org/record/7794984, {"references":["Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Mathematisch-Physikalischen Klasse der Koniglich Bayer Akademie der Wissenschaften, 31 (6), 1 - 105. https: // doi. org / 10.1515 / 9783486755459","Clark A. M. (1965). Japanese and other ophiuroids from the collections of the Mu ¨ nich Museum. Bulletin of the British Museum (Natural History) Zoology, 13, 37 - 71. https: // doi. org / 10.5962 / p. 271717","Hendler, G. (1996) Taxonomic atlas of the benthic fauna of the Santa Maria Basin and Western Santa Barbara Channel. Class Ophiuroidea. Santa Barbara Museum of Natural History, 14, 113 - 179.","Maluf, L. Y. (1988) Composition and distribution of the central Eastern Pacific Echinoderms. Natural History Museum of Los Angeles County, Technical Report, 2, 1 - 306.","Duffy, G. A., Lundsten, L., Kuhnz, L. A & Paull, C. K. (2014) A comparison of megafaunal communities in five submarine canyons off Southern California, USA. Deep-Sea Research II, 104 (2014), 259 - 266. https: // doi. org / 10.1016 / j. dsr 2.2013.06.002","Stohr, S., O'Hara, T. & Thuy, B. (2022) World Ophiuroidea database. Available from: http: // marinespecies. org / aphia. php? p = search (accessed 15 April 2022)","Honey-Escandon, M., Solis-Marin, F. A. & Laguarda-Figueras, A. (2008) Equinodermos (Echinodermata) del Pacifico Mexicano. Revista de Biologia Tropical, 56 (3), 57 - 73."]}

Astrodia excavata (Lütken & Mortensen, 1899) Fig. 2A‒G Asteronyx excavata Lütken & Mortensen, 1899: 185‒186, pl. 22, figs. 2‒6.—H.L. Clark 1913: 219; 1923: 157.— Döderlein 1927: 59, 98. Astrodia excavata. Okanishi & Fujita 2014: 192‒195, figs. 5‒7. Material examined. 58 individuals at eight stations. TALUD IV, Sta. 19, 1 ind. (ICML-EMU-11094). TALUD VIII, Sta. 11, 1 ind. (ICML-EMU-11096). TALUD XII, Sta. 23, 1 ind. (ICML-EMU-11093); Sta. 27, 17 ind. (ICML-EMU-11114); Sta. 28, 1 ind. (ICML-EMU-11097). TALUD XV, Sta. 23, 6 ind. (ICML-EMU-11100); Sta. 24, 26 ind. (ICML-EMU-11099), 1 ind. (ICML-EMU-11101), and 3 ind. (ICML-EMU-11697). TALUD XVIB, Sta. 17, 1 ind. (ICML-EMU-11102). Comparative material. Asteronyx excavata Lütken & Mortensen, 1899, lectotype, 1 ind.: MCZ OPH-2817. Paralectotype, 1 ind.: USNM 19598. Syntype, 1 ind.: USNM 19599 (Supplementary file 2). Description (ICML-EMU-11099). DD = 24.7 mm. Disc five-lobed, indented interradially. Dorsal disc covered with thickened skin, lacking scales. RS coarse, surrounded by epidermal ossicles, very prominent, almost reaching the center of the disc (Fig. 2A). Ventral interradii covered by integument and external ossicles. Genital slits oval, restricted to proximal-middle part, elongated, covering approximately 3/4 of the interradius (Fig. 2B). OSh broader than long, triangular. One madreporite, larger than OSh. AdSh broader than long, with rounded edges, meeting or almost meeting proximally. Jaws bearing six papillae at each side; OPa four, granule-like, distalmost papilla larger, rectangular-shaped; TPa two at jaw tips, spiniform, larger than OPa. Teeth several, similar to TPa (Fig. 2C). Arms entirely covered by integument, coiled, thick, gradually narrowing distally. LAP located on the ventral lateral side of vertebrae, bar-like, prominent (Fig. 2D). First to fourth tentacle pores lacking ArSp; fifth to ninth with one ArSp (Fig. 2E); subsequent pores with 3‒4 ArSp, 2‒3 serrated, one ventralmost elongated (approximately 1.5 VAP in length), bulbous, serrated at the tip, not hooked (Fig. 2F). TSc lacking. Color pattern brownish-beige (ethanol preservation) (Fig. 2A‒G). Habitat and distribution. California, USA to Mexico (Luke 1982; Granja-Fernández et al. 2015); doubtful record in Peru (Granja-Fernández & Hooker 2020); 267‒ 1,273 m depth (Okanishi & Fujita 2014), associated with rocks and gorgonians (Lütken & Mortensen 1899; H.L. Clark 1923). The material examined is from off western Baja California and Baja California Sur, the southern Gulf of California, and off Colima; 530‒ 1,245 m depth, associated with unidentified gorgonians. Remarks. In Mexico, Astrodia excavata has been recorded in western Baja California and Baja California Sur, the Gulf of California, and Marias Islands (Granja-Fernández et al. 2015). Present records in Colima represent a significant extension of its distribution to the south (to 18º33′43″N; 103º57′45″W) in western Mexico. GranjaFernández & Hooker (2020) suggested that the Peruvian record of A. excavata is doubtful and needs taxonomical confirmation. If further revision of the material from Peru indicates that this record is incorrect, then Colima (TALUD XII, Sta. 23) will be the southernmost distribution limit for this species., Published as part of Granja-Fernández, Rebeca, Hendrickx, Michel E., Rangel-Solís, Pedro Diego & López-Pérez, Andrés, 2023, Deep-sea Ophiuroidea (Echinodermata) collected during the TALUD cruises in western Mexico, pp. 1-71 in Zootaxa 5259 (1) on page 16, DOI: 10.11646/zootaxa.5259.1.1, http://zenodo.org/record/7794984, {"references":["Lu ¨ tken, C. F. &. Mortensen, T. (1899) The Ophiuridae. Memoirs of the Museum of Comparative Zoology at Harvard College, 23 (2), 93 - 208.","Clark, H. L. (1913) Echinoderms from Lower California, with descriptions of new species. Bulletin of the American Museum of Natural History, 32, 185 - 236. https: // doi. org / 10.5962 / bhl. title. 1734","Clark, H. L. (1923) Echinoderms from Lower California with descriptions of new species: supplementary report. Bulletin of the American Museum of Natural History, 48 (6), 147 - 163.","Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Mathematisch-Physikalischen Klasse der Koniglich Bayer Akademie der Wissenschaften, 31 (6), 1 - 105. https: // doi. org / 10.1515 / 9783486755459","Okanishi, M. & Fujita, T. (2014) A taxonomic review of the genus Astrodia (Echinodermata: Ophiuroidea: Asteronychidae). Journal of the Marine Biological Association of the United Kingdom, 94 (1), 187 - 201. https: // doi. org / 10.1017 / S 0025315413001331","Luke, S. R. (1982) Catalog of benthic invertebrate collections, Echinodermata. Scripps Institution of Oceanography series, no. 82 - 5, University of California, 66 pp.","Granja-Fernandez, R., Herrero-Perezrul, M. D., Lopez-Perez, R. A., Hernandez-Morales, A. & Rangel-Solis, P. D. (2015) A literature review of the Ophiuroidea (Echinodermata) from the Pacific coast of Mexico. Revista de Biologia Tropical, 63 (2), 37 - 47.","Granja-Fernandez, R. & Hooker, Y. (2020). Revisiting the diversity and distribution of the ophiuroids (Echinodermata: Ophiuroidea) from Peru. Zootaxa, 4766 (4), 539 - 556. https: // doi. org / 10.11646 / zootaxa. 4766.4.2"]}

Asteronyx loveni Müller & Troschel, 1842 Fig. 1G‒M Asteronyx loveni Müller & Troschel, 1842: 119‒120, pl. 10, figs. 3‒5.—H.L. Clark 1913: 219.— Döderlein 1927: 59‒63, pl. 7, figs. 7‒8.— Kyte 1969a: 1737.— Lambert & Austin 2007: 71‒72, fig. 27.— Okanishi et al. 2011: 370‒371, fig. 2; 2017: 6‒12, figs. 1‒6. Asteronyx locardi Koehler, 1895: 88. Asteronyx dispar Lütken & Mortensen, 1899: 185, pl. 21, figs. 1‒2.—H.L. Clark 1913: 218. Asteronyx cooperi Bell, 1909: 22. Ophiuropsis lymani Studer, 1884: 85, pl. 5, figs. 12a‒d. Ophiuraster patersoni Litvinova, 1998: 441‒443, fig. 3. See Paterson (1985) for other synonymous records. Material examined.11 individuals at six stations. TALUD VI, Sta. 34, 1 ind. (ICML-EMU-11115). TALUD VIII, Sta. 11, 2 ind. (ICML-EMU-11110). TALUD IX, Sta. 21B, 1 ind. (ICML-EMU-9012). TALUD X, Sta. 22, 2 ind. (ICML-EMU-11112). TALUD XII, Sta. 29, 3 ind. (ICML-EMU-11111) and 1 ind. (ICML-EMU-11698). TALUD XIII, Sta. B, 1 ind. (ICML-EMU-11113). Comparative material. Asteronyx dispar Lütken & Mortensen, 1899, syntypes, 15 ind.: MCZ OPH-2816, MCZ OPH-2875, MCZ OPH-2876, USNM 19592, USNM 19593, USNM 19595, USNM 19596, USNM 19597 (Supplementary file 2). Description (ICML-EMU-11111). DD = 23 mm. Disc subpentagonal, indented interradially. Dorsal disc covered with thickened skin and sparse epidermal circular ossicles, lacking scales. RS clearly multilayered, elongated, thin, prominent distally, almost reaching the center of the disc (Fig. 1G). Ventral interradii entirely covered by integument with circular-shaped epidermal ossicles. Genital slits round, restricted to proximal part of the interradius, short, covering approximately 1/6 of interradius. OSh not evident (Fig. 1H). One small circular madreporite.AdSh broader than long, rectangular with rounded edges, meeting in front of OSh. Jaws bearing seven papillae at each side; OPa four, granule-like; TPa three at jaw tips, spiniform, larger than OPa, separated. Teeth several, similar to TPa (Fig. 1I). Arms entirely covered by integument, coiled, gradually narrowing distally (Fig. 1J); two arms wider and slightly shorter than the remaining three. LAP located on the ventral lateral side of vertebrae, rounded, prominent (Fig. 1K). First tentacle pore lacking ArSp; second with one ArSp; subsequent pores gradually reaching up to 6‒7 ArSp in the middle of the arm, hook-shaped, serrated (Fig. 1K). Middle part of the arm with ventralmost ArSp very elongated (approximately two VAP in length), bulbous (Fig. 1L). TSc lacking. Color pattern yellowish-brown (ethanol preservation) (Fig. 1G‒M). Habitat and distribution. Widely distributed in deep waters worldwide, except polar regions (Paterson 1985). In the eastern tropical Pacific, A. loveni has been reported from Mexico, Panama, and the Galapagos Islands (Lütken & Mortensen 1899; Maluf 1991; Granja-Fernández et al. 2015); 100‒ 4,721 m, but more common at 200‒ 2,000 m depth (Paterson 1985; Okanishi et al. 2018). Associated with gorgonians and Pennatulacea (Fujita & Ohta 1988). The material of the TALUD cruises is from the southern Gulf of California and off Jalisco; 920‒ 1,643 m depth, associated with unidentified gorgonians. Remarks. Asteronyx loveni has been recorded in Mexico in the Gulf of California and off western Baja California and Baja California Sur (Granja-Fernández et al. 2015). During the TALUD cruises it was collected further south, off Jalisco (19º19′37″N; 105º26′20″W), which represents a significant extension of its distribution in western Mexico. Some of the TALUD specimens were associated with unidentified gorgonians. The arms of A. loveni have a specific function since the two wider arms firmly attach to the substrate (the gorgonians in this case), and the remainder, long and slender arms, extend into the water column to collect particles used for feeding (Paterson 1985; Fujita & Ohta 1988). Genetic data show considerable diversity suggesting that A. loveni might be a complex of several closely related species (Christodoulou et al. 2019)., Published as part of Granja-Fernández, Rebeca, Hendrickx, Michel E., Rangel-Solís, Pedro Diego & López-Pérez, Andrés, 2023, Deep-sea Ophiuroidea (Echinodermata) collected during the TALUD cruises in western Mexico, pp. 1-71 in Zootaxa 5259 (1) on page 14, DOI: 10.11646/zootaxa.5259.1.1, http://zenodo.org/record/7794984, {"references":["Mu ¨ ller, J. H. & Troschel, F. H. (1842) System der Asteriden. F. Vieweg & Sohn, Braunschweig, 134 pp. https: // doi. org / 10.5962 / bhl. title. 11715","Clark, H. L. (1913) Echinoderms from Lower California, with descriptions of new species. Bulletin of the American Museum of Natural History, 32, 185 - 236. https: // doi. org / 10.5962 / bhl. title. 1734","Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Mathematisch-Physikalischen Klasse der Koniglich Bayer Akademie der Wissenschaften, 31 (6), 1 - 105. https: // doi. org / 10.1515 / 9783486755459","Kyte, M. A. (1969 a) A synopsis and key to the recent Ophiuroidea of Washington State and Southern British Columbia. Journal of the Fisheries Research Board of Canada, 26 (7), 1727 - 1741. https: // doi. org / 10.1139 / f 69 - 160","Lambert, P. & Austin, W. (2007) Brittle stars, sea urchins and feather stars of British Columbia, Southeast Alaska and Puget Sound. Royal BC Museum Handbook, Victoria, 150 pp.","Okanishi, M., Yamaguchi, K., Horii, Y., & Fujita, T. (2011) Ophiuroids of the order Euryalida (Echinodermata) from Hachijo ¯ jima Island and Ogasawara Islands, Japan. Memoirs of the Natural History Museum of Sciences Tokyo, 47, 367 - 385.","Koehler, R. (1895) Dragages profonds executes a bord du Caudan dans le Golfe de Gascogne. Rapport preliminaire sur les Echinodermes. Revue biologique du Nord de la France, 7, 439 - 496.","Lu ¨ tken, C. F. &. Mortensen, T. (1899) The Ophiuridae. Memoirs of the Museum of Comparative Zoology at Harvard College, 23 (2), 93 - 208.","Bell, F. J. (1909) Report on the echinoderma (other than holothurians) collected by Mr. J. Stanley Gardiner in the western parts of the Indian Ocean. Transactions of the Linnean Society of London, 2 nd Series, Zoology, 13, 17 - 22. https: // doi. org / 10.1111 / j. 1096 - 3642.1909. tb 00406. x","Studer, T. (1884) Verzeichnis der wahrend der Reise S. M. S. \" Gazelle \" um die Erde, 1874 - 76 gesammelten Asteriden und Euryaliden. Abhandlungen der Preussischen Akademie der Wissenschaften, 2, 1 - 64.","Litvinova, N. M. (1998) Two new species of the genus Ophiuraster (Ophiurinae, Ophiuroidea, Echinodermata) from French collections and some remarks on the genus. Zoosystema, 20 (3), 439 - 444.","Paterson, G. L. J. (1985) The deep-sea Ophiuroidea of the North Atlantic Ocean. Bulletin of the British Museum (Natural History) Zoology, 49 (1), 1 - 162.","Maluf, L. Y. (1991) Echinoderm fauna of the Galapagos Islands. In: James, M. J. (Ed.), Galapagos marine invertebrates: taxonomy, biogeography, and evolution in Darwin's Islands. Plenum, New York, New York, pp. 345 - 367. https: // doi. org / 10.1007 / 978 - 1 - 4899 - 0646 - 5 _ 17","Granja-Fernandez, R., Herrero-Perezrul, M. D., Lopez-Perez, R. A., Hernandez-Morales, A. & Rangel-Solis, P. D. (2015) A literature review of the Ophiuroidea (Echinodermata) from the Pacific coast of Mexico. Revista de Biologia Tropical, 63 (2), 37 - 47.","Okanishi, M., Sentoku, A., Martynov, A. & Fujita, T. (2018) A new cryptic species of Asteronyx Mu ¨ ller & Troschel, 1842 (Echinodermata: Ophiuroidea), based on molecular phylogeny and morphology, from off Pacific Coast of Japan. Zoologischer Anzeiger, 274 (2018), 14 - 33. https: // doi. org / 10.1016 / j. jcz. 2018.03.001","Fujita, T. & Ohta, S. (1988) Photographic observations of the life style of a deep-sea ophiuroid Asteronyx loveni (Echinodermata). Deep-Sea Research, 35 (12), 2029 - 2043. https: // doi. org / 10.1016 / 0198 - 0149 (88) 90123 - 9","Christodoulou, M., O'Hara, T. D., Hugall, A. F. & Martinez-Arbizu, P. (2019) Dark ophiuroid biodiversity in a prospective abyssal mine field. Current Biology Report, 29, 3909 - 3912. https: // doi. org / 10.1016 / j. cub. 2019.09.012"]}

Deep-sea ophiuroids were collected by the manned submersible ‘Shenhaiyongshi’ from the South China Sea at depths of 500–3550 m, in 2017 to 2020. A total of 18 species were identified, including three new species and eight new records, increasing the total number of species known from the South China Sea to 304. Most of the ophiuroids recorded from the South China Sea were found in shallow waters (77.9%) and a few of them occurred only in deep water (20.4%). Three new species are described as Ophiacantha aster sp. nov., Ophiomoeris petalis sp. nov. and Ophiopristis shenhaiyongshii sp. nov. We provide comprehensive descriptions of morphological features, including characteristics of the arm skeletons, and a phylogenetic analysis based on COI and 16S sequences. Overall intraspecific and interspecific genetic distance variations among the families found in this study were 0.5% to 2.47% and 1.16% to 44.16%, respectively, along the South Pacific region to the South China Sea. Our phylogenetic analysis suggested that COI partial genes resolved the interspecies complexity in the class Ophiuroidea better than 16S partial genes. The order Euryalida had low interspecies genetic distance variation within the class Ophiuroidea. The present study suggests a high probability that species of Asteroschema and Gorgonocephalus are more widely spread around the Indo-Pacific region than previously expected.

Asteronyx luzonicus Döderlein, 1927 Figs 4–6 Asteronyx luzonicus Döderlein, 1927: 64, pl. 7 figs 4–5, 6a–d. Asteronyx luzonicus – Baker et al. 2018: 7–8, figs 4–5. Material examined CHINA • 1 spec.; South China Sea, SE of Hainan Island, seamount; 18°31.76′ N, 112°40.56′ E; depth 1167 m; 27 Jun. 2019; collection event: stn SC002; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198757, MZ 203265; IDSSE EEB-SW0003 • 1 spec.; same collection data as for preceding; depth 1162 m; 8 Jul. 2019; collection event: stn SC002; MSV Shenhaiyongshi leg.; preserved in -80°C; IDSSE EEB-SW0032. Description (IDSSE EEB-SW 0003) MEASUREMENTS. Disc diameter 13.5 mm. DiSC. Flat, pentagonal. Entire dorsal disc covered by smooth, transparent, naked skin, but some small calcified scales between radial shields. Skin on center of dorsal disc becoming mesh-like and less smooth than at periphery of disc. Radial shields narrow, elongate, separate, covered by skin and extending to near disc center, but not meeting in center (Fig. 4A). Ventral (oral) surface of disc also covered by smooth skin (Fig. 4B). Oral shields slightly triangular. Adoral shield large, wider than long and slightly concave at distal margin, bordering proximal end of a depressed area near genital slit. Two tooth papillae, large and pointed, three smaller pointed lateral oral papillae, teeth also pointed. Two small, short, well separated genital slits in each ventral interradius (Fig. 4C–D). ARMS. Simple, similar in size and length, five in number, with no abrupt change in width proximally, gradually tapering toward arm tip. No dorsal arm plates, arm covered with smooth translucent skin, leaving vertebrae visible (Fig. 4E). Ventral and lateral arm plates concealed by thick skin but slightly visible on proximal arm (Fig. 4F). Lateral arm plates meet at ventral midline, spines at ventrolateral margin extending onto ventral surface (Figs 4F–G, 5A–B). Starting from first free arm segment beyond disc, first two to three arm segments without spines at tentacle pores (Fig. 4B–C); third to fourth arm segments with one or two short arm spines, becoming hook-shaped or with one secondary tooth (Fig. 4C). Following tentacle pores with two to five hook-shaped arm spines and only uppermost arm spine elongated to simple hook shape, but ventralmost spines with one secondary tooth (Fig. 5D). Length of all arm spines decreasing to approximately half length of corresponding arm segment in middle of arm. On distal third of arm, arm spines half as long as corresponding arm segment and transforming into hooks without secondary tooth, except ventralmost arm spine. Ventralmost arm spine becoming cylindrical, blunt with thorny tip, as long as one arm segment (Fig. 5A–F). Tube foot elongate, cylindrical, slender, as long as an arm segment and positioned close to ventralmost arm spine (Fig. 5A–C). COLOR. Dorsal disc light brown in center, naked skin between radial shields darker, radial shields whitish brown; ventral interradial areas light brown; arms whitish brown above and below (Fig. 4). OSSiCLE MORPHOLOGY. Lateral arm plate curved around vertebrae, bearing five spine articulations, each with small muscle opening, but lacking a separate nerve opening (Fig. 6A–C). Arm spine articulations at distal edge of lateral plate, raised outwards, pointing distalwards. A depression on inner side of lateral arm plate (Fig. 6B). Vertebrae with streptospondylous articulation, ventral side with a longitudinal groove along midline and no oral bridge (Fig. 6D–H). Remarks The here examined specimens were collected on a deep-sea seamount, attached to a gorgonian. Asteronyx luzonicus was first described by Döderlein (1927) from the Philippines. However, there are few published descriptions of A. luzonicus (Baker et al. 2018) and the species has not been imaged well before. Döderlein (1927) mentioned an elongated, slender ventralmost arm spine, as long as an arm segment, parallel to the longitudinal arm axis, as a distinguishing morphological feature of A. luzonicus, because in other species of Asteronyx, the ventralmost spine is usually placed transversally to the longitudinal axis of the arm and often reaches twice the length of an arm segment. Dried specimens of A. luzonicus are particularly strikingly dark and a main distinguishing morphological feature of A. luzonicus is the presence of black spots on the disc of sexually mature specimens (Baker et al. 2018). Specimens from our collection were not sexually mature and only had darker skin on both the dorsal and ventral disc, but they concur with a Baker et al. (2018) in the calcified scales. Recent studies on species of Asteronyx suggested that features of the dorsal disc surface, as well as the position and length of the genital slit may be important characters to distinguish the six species in this genus (Okanishi et al. 2018). Döderlein did not describe the dorsal disc surface and mentioned few morphological characters to distinguish his new species from other species in the genus Asteronyx, i.e., in characters of the tentacle scale and darker disc spots in sexually mature specimens. Specimens of Asteronyx in our collection are immature but similar in size. Therefore, a comprehensive morphological analysis can be used to distinguish A. loveni from A. luzonicus such as: hook-shaped arm spines with at most one secondary tooth along the arm in A. luzonicus, whereas A. loveni has hook-shaped arm spines with more than one secondary tooth (Figs 2F, 4F, 5); in A. luzonicus the dorsal disc surface is flatter than in A. loveni and becoming rough, mesh-like in the center (Figs 2A, 4A); the first two to three arm segments in A. luzonicus have only a tentacle foot and no arm spine, but in A. loveni only the first arm segment is without a single spine (Figs 2B, 4B). The ventralmost arm spine is as long as one arm segment, cylindrical, tapered, with a blunt, thorny tip (Fig. 5H–J). Asteronyx reticulata Okanishi, Martynov & Fujita, 2018 is similar to A. luzonicus, but differs in having mesh-like skin on its ventral disc (Okanishi et al. 2018). Distribution 109–2963 m depth. South China Sea, Sibuyan Sea, Samar Sea, Bohol Sea, East China Sea, Andaman Sea, Southern Mozambique (Baker et al. 2018). Family Euryalidae Gray, 1840 Genus Asteroschema Örsted & Lütken in Lütken, 1856, Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, pp. 1-95 in European Journal of Taxonomy 810 (1) on pages 14-18, DOI: 10.5852/ejt.2022.810.1723, http://zenodo.org/record/6419522, {"references":["Doderlein L. 1927. Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse 31 (6): 1 - 106.","Baker A. N., Okanishi M. & Pawson D. L. 2018. Euryalid brittle stars from the international Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida). Zootaxa 4392 (1): 1 - 27. https: // doi. org / 10.11646 / zootaxa. 4392.1.1","Okanishi M., Sentoku A., Martynov A. & Fujita T. 2018. A new cryptic species of Asteronyx Muller and Troschel, 1842 (Echinodermata: Ophiuroidea), based on molecular phylogeny and morphology, from off Pacific coast of Japan. Zoologischer Anzeiger 274: 14 - 33. https: // doi. org / 10.1016 / j. jcz. 2018.03.001"]}

Gorgonocephalus cf. dolichodactylus Döderlein, 1911 Figs 11–12 Gorgonocephalus dolichodactylus Döderlein, 1911: 34–36, pl. 1 figs 4–5, pl. 7 figs 3, 4a–b. Gorgonocephalus dolichodactylus – Döderlein 1927: 27, 52. — Matsumoto 1915: 73, fig. 20. — Baker 1980: 52, figs 18a, 20, 30. — Liao & Clark 1995: 171, fig. 75. — McKnight 2000: 45–46, pl. 20. Material examined CHINA • 1 spec.; South China Sea, Zhongsha Islands, seamount; 13°36.00′ N, 114°34.49′ E; depth 1340 m; 30 Mar. 2020; collection event: stn SC008; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198760; IDSSE EEB-SW0006. Remarks The disc diameter was 67 mm. Our specimen is similar to the holotype description by Döderlein (1911) and the description in Liao & Clark (1995), but showed some morphological variations, especially on the disc (Fig. 11). Therefore, we hesitate to fully associate our specimen with G. dolichodactylus. The original description and the description in Liao & Clark (1995) mention small granules on both the dorsal and ventral disc, but the present specimen is completely naked except for the radial shields (Fig. 11A–E), which are covered by scattered granules (Fig. 11F). Pedicellarial bands are formed by approximately 12 articulating tubercles at the curved distal end of the baseplate (Fig. 12B), and these articulations have a single foramen (Fig. 12C). The distal end of the baseplate internal side becomes curved with perforations on the ventral side of the baseplate (Fig. 12B–C). The vertebrae have a streptospondylous articulation with smooth lateral furrows and no oral bridge (Fig. 12D–H). The external side of the lateral arm plate has three separate tubercle-shaped articulations with a single opening and one large muscle opening at the edge. Gorgonocephalus dolichodactylus was first recorded from the South China Sea in southeastern Hainan, at a depth of 1100 m, in 1959. Distribution 146–1357 m depth. South China Sea, Japan, Korea, Philippines, Australia and New Zealand (Liao 2004; OBIS 2021). Order Ophiurida Müller & Troschel, 1840 sensu O’Hara et al. 2017 Suborder Ophiomusina O’Hara, Hugall, Thuy, Stöhr & Martynov, 2017 Family Ophiomusaidae O’Hara, Stöhr, Hugall, Thuy & Martynov, 2018 Genus Ophiomusa Hertz, 1927, Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, pp. 1-95 in European Journal of Taxonomy 810 (1) on pages 25-28, DOI: 10.5852/ejt.2022.810.1723, http://zenodo.org/record/6419522, {"references":["Doderlein L. 1911. Uber japanische und andere Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse Suppl. 5 (2): 1 - 123.","Doderlein L. 1927. Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse 31 (6): 1 - 106.","Matsumoto H. 1915. A new classification of the Ophiuroidea: with descriptions of new genera and species. Proceedings of the Academy of Natural Sciences of Philadelphia 67: 43 - 92.","Baker A. N. 1980. Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the South-west Pacific Ocean. New Zealand Journal of Zoology 7 (1): 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","Liao Y. & Clark A. M. 1995. The Echinoderms of Southern China. Science Press, Beijing.","McKnight D. G. 2000. The marine fauna of New Zealand: basket-stars and snake-stars (Echinodermata: Ophiuroidea: Euryalinida). NIWA Biodiversity Memoir 115: 1 - 79.","Liao Y. 2004. Echinodermata: Ophiuroidea. Fauna Sinica: Zoology of China Invertebrates 40. Science Press, Beijing.","OBIS 2021. Ocean Biodiversity Information System. Available from www. obis. org [accessed 15 Aug. 2021].","O'Hara T. D., Hugall A. F., Thuy B., Stohr S. & Martynov A. V. 2017. Restructuring higher taxonomy using broad-scale phylogenomics: the living Ophiuroidea. Molecular Phylogenetics and Evolution 107: 415 - 430. https: // doi. org / 10.1016 / j. ympev. 2016.12.006","O'Hara T. D., Stohr S., Hugall A. F., Thuy B. & Martynov A. 2018. Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification. European Journal of Taxonomy 416: 1 - 35. https: // doi. org / 10.5852 / ejt. 2018.416","Hertz M. 1927. Die Ophiuroiden der Deutschen Tiefsee-Expedition. I. Chilophiurida Matsumoto (Ophiolepididae, Ophioleucidae, Ophiodermatidae, Ophiocomidae). Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition auf dem Dampfer Valdivia, 1898 - 1899 22 (3): 59 - 122."]}

Asteronyx loveni Müller & Troschel, 1842 Figs 2–3 Asteronyx loveni Müller & Troschel, 1842: 119–120, pl. 10 figs 3–5. Ophiuropsis lymani Studer, 1884: 55–46, pl. 5 fig. 12a–d. Asteronyx dispar Lütken & Mortensen, 1889: 185, pls 21–22. Asteronyx locardi Koehler, 1895: 470–471, fig. 10. Asteronyx cooperi Bell, 1909: 22. Ophiuraster patersoni Litvinova, 1998: 441–444, fig. 3. Asteronyx loveni – Döderlein 1927: 59, 97, pl. 7 figs 7–8. — Baker 1980: 12, 16–18, figs 2–3. — Liao & Clark 1995: 165–166, fig. 71. — McKnight 2000: 8, 13–15, pl. 1. — Olbers et al. 2019: 49–50, fig. 23. Ophiuraster patersoni – Stöhr 2005: 545–546, fig. 1. Material examined CHINA • 1 spec.; South China Sea, SE of Hainan Island, seamount; 18°31.76′ N, 112°40.56′ E; depth 1167 m; 27 Jun. 2019; collection event: stn SC002; MSV Shenhaiyongshi leg.; preserved in -80°C; GenBank: MZ 198756, MZ 203264; IDSSE EEB-SW0002. Remarks Disc diameter 11 mm and collected attached to a gorgonian species. Our specimen is similar to the holotype description by Müller & Troschel (1842) and later published descriptions (Baker 1980; McKnight 2000; Olbers et al. 2019) (Fig. 2). Vertebrae with a streptospondylous articulation and the lateral arm plate bears four to five spine articulations, which lack a separate nerve opening (Fig. 3). Species of Asteronyx are usually found on mud and sand, associated with gorgonians and pennatulids. In 1959 and from 1976 to 1981, 52 specimens of A. loveni were collected from the East and South China seas, at depths of 510–1100 m. Asteronyx loveni was first reported from the South China Sea by Chang et al. (1962). Distribution 62–4721 m depth. Global, except Arctic and Antarctic (Olbers et al. 2019; OBIS 2021)., Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, pp. 1-95 in European Journal of Taxonomy 810 (1) on pages 11-12, DOI: 10.5852/ejt.2022.810.1723, http://zenodo.org/record/6419522, {"references":["Muller J. & Troschel F. H. 1842. System der Asteriden. 1. Asteriae. 2. Ophiuridae. Vieweg, Braunschweig, Germany.","Studer T. 1884. Verzeichnis der wahrend der Reise S. M. S. ' Gazelle' um die Erde, 1874 - 76 gesammelten Asteriden und Euryaliden. Abhandlungen der preussischen Akademie der Wissenschaften 2: 1 - 64.","Lutken C. F. & Mortensen T. 1889. Reports on an exploration off the west coasts of Mexico, Central and Southern America and off the Galapagos Islands. XXV. The Ophiuridae. Memoirs of the Museum of Comparative Zoology 23 (2): 97 - 208.","Koehler R. 1895. Dragages profonds executes a bord du Caudan dans le Golfe de Gascogne. Rapport preliminaire sur le echinodermes. Revue biologique du Nord de la France 7: 439 - 49.","Bell F. J. 1909. Report on the Echinoderma (other than holothurians) collected by Mr. J. Stanley Gardiner in the western parts of the Indian Ocean. Transactions of the Linnean Society of London, Series 2 2: 17 - 22. Available from https: // www. biodiversitylibrary. org / page / 16398922 [accessed 16 Feb. 2022].","Litvinova N. M. 1998. Two new species of the genus Ophiuraster (Ophiurinae, Ophiuroidea, Echinodermata) from French collections and some remarks on the genus. Zoosystema 20 (3): 439 - 444.","Doderlein L. 1927. Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse 31 (6): 1 - 106.","Baker A. N. 1980. Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the South-west Pacific Ocean. New Zealand Journal of Zoology 7 (1): 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","Liao Y. & Clark A. M. 1995. The Echinoderms of Southern China. Science Press, Beijing.","McKnight D. G. 2000. The marine fauna of New Zealand: basket-stars and snake-stars (Echinodermata: Ophiuroidea: Euryalinida). NIWA Biodiversity Memoir 115: 1 - 79.","Olbers J. M., Griffiths C. L., O'Hara T. D. & Samyn Y. 2019. Field guide to the brittle and basket stars (Echinodermata: Ophiuroidea) of South Africa. Abc Taxa 19: 1 - 354. Available from http: // www. abctaxa. be / volumes / volume _ 19 _ fieldguide-brittle-and-basket-stars [accessed 16 Feb. 2022].","Stohr S. 2005. Who's who among baby brittle stars (Echinodermata: Ophiuroidea): postmetamorphic development of some North Atlantic forms. Zoological Journal of the Linnean Society 143 (4): 543 - 576. https: // doi. org / 10.1111 / j. 1096 - 3642.2005.00155. x","Chang F. Y., Liao Y. L. & Wu B. L. 1962. Euryaliae of the China Sea. Acta Zoologica Sinica 14: 53 - 68.","OBIS 2021. Ocean Biodiversity Information System. Available from www. obis. org [accessed 15 Aug. 2021]."]}

Gorgonocephalus chilensis novaezelandiae Mortensen, 1924 Figs 9–10 Gorgonocephalus chilensis var. novaezelandiae Mortensen, 1924: 109–110, pl. 4 fig 1. Gorgonocephalus chilensis – Baker 1980: 51–52. — McKnight 2000: 45–46, pl. 19. [non G. chilensis chilensis Philippi, 1858] Material examined CHINA • 1 spec.; South China Sea, SE of Zhongsha Islands, seamount; 13° 58.68′ N, 114° 52.09′ E; depth 1550 m; 25 Sep. 2020; collection event: stn SC013; MSV Shenhaiyongshi leg.; preserved in 95% ethanol; GenBank: MZ 198761; IDSSE EEB-SW0007. Description (IDSSE EEB-SW 0007) MEASUREMENTS. Disc diameter 15.5 mm. DiSC. Dorsal disc slightly inflated, interradials slightly indented. Radial shields elongated and narrow, extending nearly toward center of disc but not meeting in center, tapering at distal ends, densely covered by large, tall conical granules. Skin between radial shields also covered by conical granules, but less dense and smaller than on radial shields, but disc center covered with compacted conical granules. Disc periphery covered with few larger conical granules (Fig. 9A–F). Ventral disc covered with small, scattered, low granules, extending onto oral area (Fig. 9E). Genital slits conspicuous, interradial margin covered by two irregular rows of larger, higher than wide granules (Fig. 9D). Single madreporite. Oral area covered by smooth skin, partly exposing adoral shield outlines and few scattered smaller granules (Fig. 9E). Adoral shields short, square. Oral papillae spiniform (Fig. 9E). ARMS. Branched at least six to seven times, flexible dorso-ventrally, flat ventrally, high rounded dorsally (Fig. 9A). Ventral arm along first branch and near base covered by smooth skin, distalwards scattered with smaller granules (Fig. 9G). Dorsal arm surface covered by domed scales, on proximal segments with naked scales and naked areas corresponding to pedicellarial bands. Dorsal arm surface densely covered by compact granules after second arm fork. Pedicellarial bands start at second arm fork with three to four isolated clumps on each side of arm and becoming continuous across arm. From sixth arm fork, raised pedicellarial bands give an annulated appearance to arm (Fig 9H). First arm segment lacks spines, next three with two arm spines, next nine to ten with three arm spines and thereafter four arm spines per segment, decreasing to three after fifth branch (Fig. 9G, I–J). Ventral arm spines smaller, slightly flattened, unevenly pointed, distally turning into multi-toothed hooks (Fig. 9J–L). Pedicellariae with small secondary tooth (Fig. 9K–L). COLOR. Creamy white in alcohol specimen, with light brown disc and darker arms when alive (Fig. 9A–B). OSSiCLE MORPHOLOGY. Pedicellarial band formed by approximately six articulating tubercles on middle arm region and eight articulations at curved distal end (Fig. 10A–B). Tubercles form two parallel rows with single foramen (Fig. 10A–B). Ventral arm spines distally transformed into hooks with two or three secondary teeth (Fig. 10C). Pedicellariae on pedicellarial band with single secondary tooth and apophysis (Fig. 10D). Pedicellariae on pedicellarial band differ from ventral arm spine by smooth apophysis. Vertebrae with hourglass-shaped streptospondylous articulation with smooth lateral furrows (Fig. 10E–I). Paired openings in lateral side of vertebrae for lateral water canals, no oral bridge (Fig. 10F–G). Remarks The subspecies G. chilensis novaezelandiae is currently unaccepted and considered a junior synonym of G. chilensis (Philippi, 1858) (Stöhr et al. 2021). Our molecular results (see below) place this specimen with other New Zealand material in a sister clade to G. chilensis from Antarctica and the Southern Ocean. We consider the New Zealand clade sufficiently different from the Antarctic clade to reinstate the subspecies name for it, pending further investigation that may result in raising it to full species status. For the Antarctic clade, the name G. chilensis chilensis should be used for the time being, although the type locality is in Southern Chile, and if future molecular data find the Chilean population to be in the same clade as the New Zealand and South China Sea material, a new name would need to be found for the Antarctic clade. The only morphological difference between the two subspecies mentioned by Mortensen (1924) is a sparser distribution of the dorsal disc granules in G. chilensis novaezelandiae. The specimen from the present study is smaller and thus probably younger than the holotypes of both subspecies and the New Zealand specimens described by Baker (1980) and McKnight (2000). However, McKnight (2000) also reported two specimens of the same size as ours (16 mm disc diameter) with a dense cover of disc granules. This character may either be variable or age-related. We consider it highly likely that the specimens studied by Baker (1980) and McKnight (2000) represent G. chilensis novaezelandiae. The morphological characters of our specimen varied slightly from their descriptions, particularly in the number of branches in the arms, which is size dependent. According to Baker (1980) the shields indirectly contributed to thickening the periphery of the disc, but other species of Gorgonocephalus showed a distinct gap in granulation at the end of the shields and granules on the periphery of the disc. Therefore, this morphological feature can be used to distinguish G. chilensis within the genus Gorgonocephalus. Considering other morphological characters, G. tuberosus Döderlein, 1902 is similar to G. chilensis by having a dense cover of coarse, conical, or hemispherical granules on the disc, small and closely arranged in the dorsal angle of the interradial space (Döderlein 1902). H.L. Clark (1923), Seno & Irimura (1968) and Mortensen (1936) reported on younger individuals that were attached to the mature adult individuals, which prompted H.L. Clark (1923) to consider G. chilensis as viviparous. Mortensen (1936) suggested that it is not viviparous and these younger specimens simply attached to mature specimens as a host, like larger specimens attach to gorgonians (Olbers et al. 2019). This is the first record of G. chilensis novaezelandiae from the Indo-Pacific region and far from previously recorded occurrences, which may suggest that other non-Antarctic records also belong to this subspecies. Its true bathymetric and geographic distribution is currently unclear, because most previously recorded specimens were reported as G. chilensis and need to be re-examined, preferably with molecular methods. The taxonomic value of the disc granulation should be tested by examination of a large number of specimens, which could also find other distinguishing characters. Distribution 1550–1830 m depth. New Zealand, South China Sea (Mortensen 1924; this study)., Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, pp. 1-95 in European Journal of Taxonomy 810 (1) on pages 21-25, DOI: 10.5852/ejt.2022.810.1723, http://zenodo.org/record/6419522, {"references":["Mortensen T. 1924. Echinoderms of New Zealand and the Auckland-Campbell Islands. II. Ophiuroidea. Papers from Dr Th. Mortensen's Pacific Expedition 1914 - 16. Videnskabelige Meddelelser fra Dansk naturhistorisk Forening 77: 91 - 177.","Baker A. N. 1980. Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the South-west Pacific Ocean. New Zealand Journal of Zoology 7 (1): 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","McKnight D. G. 2000. The marine fauna of New Zealand: basket-stars and snake-stars (Echinodermata: Ophiuroidea: Euryalinida). NIWA Biodiversity Memoir 115: 1 - 79.","Doderlein L. 1902. Japanische Euryaliden. Zoologischer Anzeiger 25: 320 - 326.","Clark H. L. 1923. The echinoderm fauna of South Africa. Annals of the South African Museum 13 (7): 221 - 438.","Seno J. & Irimura S. 1968. Ophiuroidea collected from around the Ross Sea in 1964 with description of a new species. Journal of the Tokyo University of Fisheries 9 (2): 147 - 154.","Mortensen T. 1936. Discovery Reports: Echinoidea and Ophiuroidea. Cambridge University Press, Cambridge, UK.","Olbers J. M., Griffiths C. L., O'Hara T. D. & Samyn Y. 2019. Field guide to the brittle and basket stars (Echinodermata: Ophiuroidea) of South Africa. Abc Taxa 19: 1 - 354. Available from http: // www. abctaxa. be / volumes / volume _ 19 _ fieldguide-brittle-and-basket-stars [accessed 16 Feb. 2022]."]}

Asteroschema horridum Lyman, 1879 Figs 7–8 Asteroschema horridum Lyman, 1879: 66. Asteroschema horridum – Lyman 1882: 275. — Baker 1980: 20, fig. 4. — McKnight 2000: 17, pl. 3. Material examined CHINA • 1 spec.; South China Sea, SE of Zhongsha Islands complex, seamount; 13°58.68′ N, 114°52.09′ E; depth 1550 m; 25 Sep. 2020; collection event: stn SC013; MSV Shenhaiyongshi leg.; preserved in 95% ethanol; GenBank: MZ 198759; IDSSE EEB-SW0005 • 1 spec.; South China Sea, SE of Hainan Island, seamount; 18°41.95′ N, 113°33.08′ E; depth 1070 m; 29 Mar. 2018; collection event: stn SC019; MSV Shenhaiyongshi leg.; preserved in -80°C; IDSSE EEB-SW0033. Description (IDSSE EEB-SW 0005) MEASUREMENTS. Disc diameter 12.5 mm, length of arms from 180 to 191 mm. DiSC. Flat, interradially deeply excavated and small in relation to total body size of specimen. Disc covered with small, tumid, irregular scales, but larger on ventral than on dorsal disc. Conically tumid scales on radial shields, forming tubercles with finely thorny tip (Fig. 7A–B), both shields and tubercles decreasing in size towards disc center. Radial shields thick, swollen, widely separated distally, convergent proximally and with additional smaller scales and tubercles. Genital slits short, vertical on ventral interradii (Fig. 7D). Seven blunt, spearhead-shaped teeth. Jaws covered with swollen scales and no true oral papillae (Fig. 7C–D). Adoral shield obscured by swollen scales, oral shield absent and oral tentacle pore covered by small tube-shaped scales. Entire oral area covered with tumid scales, higher and pointier towards margin of ventral disc (Fig. 7C). ARMS. Narrow, more cylindrical and slightly swollen in first 14–15 free arm segments (Fig. 7E). Dorsal and ventral arm also covered with more trapezoid tuberculous scales, distally tubercles more rounded and less elongated and arms with increasingly banded appearance distalwards (Fig. 7E–I). Tubercles on ventral arm slightly lower and pointier than on dorsal surface. First tentacle pore with zero to one arm spine, on second to fifth arm segments one arm spine at tentacle pores, thereafter two arm spines per pore (Fig. 7G–H). Arm spines cylindrical with thorny tip, innermost spine slightly swollen, longer than arm width, twice as long as outermost spine, with thorny tip. Outermost spine not swollen, half as long as innermost spine, tapered (Figs 7I–J, 8C). COLOR. Pale reddish-brown in alcohol specimen (Fig. 7), slightly stronger color in live specimen. OSSiCLE MORPHOLOGY. Lateral arm plates curved around vertebrae, bearing two strongly outwards curved arm spine articulations with large muscle and nerve openings (Fig. 8A–B). Vertebrae with a streptospondylous articulation, with deep slope between proximal and distal end, ventrally with longitudinal groove along midline, no oral bridge (Fig. 8D–H). Remarks Asteroschema horridum was first described by Lyman (1879), with the Kermadec Islands as the type locality (HMS ‘Challenger’ Expedition). Baker (1980) and McKnight (2000) redescribed it. The specimen from our collection was similar to Lyman’s holotype description, but differs slightly from the descriptions in Baker (1980) and McKnight (2000) in having the start of the second arm spine at the first few arm segments (beyond segments 3–6, usually beyond segment 2). This character varies among species of Asteroschema (Baker 1980). Another morphological variation was shown as the extent of swelling on the proximal arm. In the present study, the small specimen (8.2 mm) had a swollen arm for five to six segments, which is similar to Baker (1980) and McKnight (2000), but they did not mention the diameter of the disc (size of the specimen). The character of having a small, flat disc with tubercleshaped scales is one that distinguishes A. horridum from other species of Asteroschema. Asteroschema horridum is considered a close relative of A. tumidum Lyman, 1879 according to morphological aspects (Baker 1980; McKnight 2000). Previously published descriptions suggested that the morphological characters of A. horridum may vary with the size and maturity of the specimens (Baker 1980; McKnight 2000). Distribution 300–2000 m depth. South China Sea, Kermadec Islands and Norfolk Island (New Zealand), New Caledonia, Vanuatu (Coral Sea), French Polynesia (Baker 1980; McKnight 2000; OBIS 2021). Family Gorgonocephalidae Ljungman, 1867 Subfamily Gorgonocephalinae Döderlein, 1911 Genus Gorgonocephalus Leach, 1815, Published as part of Nethupul, Hasitha, Stöhr, Sabine & Zhang, Haibin, 2022, New species, redescriptions and new records of deep-sea brittle stars (Echinodermata: Ophiuroidea) from the South China Sea, an integrated morphological and molecular approach, pp. 1-95 in European Journal of Taxonomy 810 (1) on pages 18-21, DOI: 10.5852/ejt.2022.810.1723, http://zenodo.org/record/6419522, {"references":["Lyman T. 1879. Ophiuridae and Astrophytidae of the \" Challenger \" expedition. Part II. Bulletin of the Museum of Comparative Zoology 6 (2): 17 - 83.","Lyman T. 1882. Report on the Ophiuroidea. Report of the Scientific Results of the Voyage of H. M. S. Challenger 1873 - 76, Zoology 5 (1): 1 - 386.","Baker A. N. 1980. Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the South-west Pacific Ocean. New Zealand Journal of Zoology 7 (1): 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","McKnight D. G. 2000. The marine fauna of New Zealand: basket-stars and snake-stars (Echinodermata: Ophiuroidea: Euryalinida). NIWA Biodiversity Memoir 115: 1 - 79.","OBIS 2021. Ocean Biodiversity Information System. Available from www. obis. org [accessed 15 Aug. 2021].","Doderlein L. 1911. Uber japanische und andere Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-physikalische Klasse Suppl. 5 (2): 1 - 123."]}

Ophiuroids were collected by the manned submersible ‘Shenhaiyongshi’ from the deep-sea seamounts in the South China Sea and Northwest Pacific regions at 602–1920 m depth, during 2018 to 2020. A total of nine species was identified, including two new species and seven new records from the South China Sea and one new record from the Northwest Pacific region. Two new species are described as Asteroschema shenhaiyongshiisp. nov. and Asteroschema domogranulatumsp. nov. The seven new records included five species from the genus Asteroschema, and one species each from the genera Asterostegus and Astrodendrum. Comprehensive descriptions of morphological features are provided, including characteristics of the arm skeleton, as well as a phylogenetic analysis based on 16S and COI sequences. Intraspecific genetic distance ranges of Euryalida species from the present study were 0.34% to 1.38%, which was relatively low compared to other orders in the class Ophiuroidea. The present study suggests a high probability that species of the order Euryalida are more widely spread around the Indo-Pacific region than previously expected.

Five specimens of Ophiuroidea from deep-sea seamounts in the West Pacific were collected and identified as two species, Astrodia duospinasp. nov. and Astrodia abyssicola. The new species, Astrodia duospinasp. nov., can be distinguished from its congeners by having indistinct or underdeveloped oral papillae, relatively short genital slits, crescent-shaped lateral arm plates, and plate-shaped external ossicles on the aboral surface of the disc. One specimen was identified as Astrodia abyssicola, which has been reported in the north-western Pacific and the north-eastern coast of Japan. The most recent tabular key of Astrodia was revised with two more key characteristics added, the shape and presence of oral papillae and the number of arm spines. The phylogenetic relationship of Astrodia and Asteronyx was analyzed based on 16S and COI sequences. The discovery of the two species further expanded the geographical distribution of the genus Astrodia.

Family Euryalidae Gray, 1840 Type genus Euryale Lamarck, 1816. Other genera Asteromorpha Lütken, 1869; Asteroschema Örstedt & Lütken, 1856; Asterostegus Mortensen, 1933; Astrobrachion Döderlein, 1927; Astroceras Lyman, 1879; Astrocharis Koehler, 1904; Ophiocreas Lyman, 1869; Squamophis Okanishi Okanishi, O'Hara & Fujita, 2011; Sthenocephalus Koehler, 1898; Trichaster Agassiz, 1836. Description ARM. Arm shape branched; length more than 4× disc diameter; covering with granules. Arm combs absent. Dorsal arm plate absent. Accessory dorsal arm plate absent. Ventral arm plate present or absent. Accessory ventral arm plate absent. Girdle of tiny hooks on the arms absent. Spines not all similar in shape.Atypical arm spines are hook-shaped.Arm spine cross section round. The ratio of thickness of distal ⅓ of arm spine to maximum thickness (in a given cross-sectional plane) 0.9–1. Arm spines cylindrical; at proximal segments only on ventral side of arms; predominantly erect, standing perpendicular to arm axis. Longest arm spines shorter than half a segment. Tentacle scales present; pores visible along the arm; nearly as long as wide; shorter than the spine nearby; cross section round. Position of lateral arm plate (LAP) only lateral. Dorsal and/or ventral edge(s) of LAPs without constriction (Fig. 2J). Ventral position of LAP not projecting ventro-proximalwards. Ventro-distal tip of LAP not projecting ventralwards. Arm spine articulation without dorsal and ventral lobes; restricted to (the ventral or central) portion of the distal edge; all similar. Distance between spine articulations not applicable (two spine articulation). Nerve and muscle openings separated by large, prominent ridge or regular stereom. Nerve opening approximately as large as muscle opening (Fig. 3A–B). DORSAL DISC. Disc pentagonal; flat (about same level as arms). Integument not obscuring plates. Dorsal disc with granules; with concealed primary plates; without scales; without spines. Dorsal disc scale/plate without tubercles. Radial shield present; with tubercles grown out of plate; length more than half of the disc radius; bar-like. VENTRAL DISC. Gonads not restricted to the disc (extending into the basal portion of the arms) or restricted to the disc (Asteroschema). Ventral interradii without granules/spines. Scales on ventral interradii absent. Ventral teeth single. Infradental papillae on oral plate present. Buccal scales on OP absent. Accessory oral papillae on OP absent. Lateral oral papillae on OP absent. Adoral shield spine absent. Lyman’s ossicle absent. Oral shield covering less than one third of interradius; about as long as wide. Madreporite multiple; with one pore, or with numerous pores. Adoral shield meeting in front of the oral shield. Abradial genital plate not twisted. Number of genital slits one per bursa. Genital slit shorter than half interradius. Genital papillae absent. Dental plate of equal width all over; fragmented. Dental sockets slit-shaped; equal to or more than 50% of the width. At least one socket on DP as depression or perforation without septum. Teeth flat (with round or slightly pointed tip, but never spine-like). Teeth on DP arranged as single row. VERTEBRAE. Vertebrae hourglass-shaped (streptospondylous); beyond segment 5 non-keeled; with oral bridge (Fig. 3E)., Published as part of Goharimanesh, Mona, Stöhr, Sabine, Mirshamsi, Omid, Ghassemzadeh, Fereshteh & Adriaens, Dominique, 2021, Interactive identification key to all brittle star families (Echinodermata; Ophiuroidea) leads to revised morphological descriptions, pp. 1-63 in European Journal of Taxonomy 766 (1) on pages 20-21, DOI: 10.5852/ejt.2021.766.1483, http://zenodo.org/record/5514587

Family Gorgonocephalidae Ljungman, 1867 Type genus Gorgonocephalus Leach, 1815. Other genera Asteroporpa Örstedt & Lütken, 1856; Astracme Döderlein, 1927; Astroboa Döderlein, 1911; Astrocaneum Döderlein, 1911; Astrochalcis Koehler, 1905; Astrochele Verrill, 1878; Astrochlamys Koehler, 1912; Astrocladus Verrill, 1899; Astroclon Lyman, 1879; Astrocnida Lyman, 1872; Astrocrius Döderlein, 1927; Astrocyclus Döderlein, 1911; Astrodendrum Döderlein, 1911; Astrodictyum Döderlein, 1927; Astroglymma Döderlein, 1927; Astrogomphus Lyman, 1869; Astrogordius Döderlein, 1911; Astrohamma Döderlein, 1930; Astrohelix Döderlein, 1930; Astroniwa McKnight, 2000; Astrophyton Fleming, 1828; Astroplegma Döderlein, 1927; Astrosierra Baker, 1980; Astrospartus Döderlein, 1911; Astrothamnus Matsumoto, 1915; Astrothorax Döderlein, 1911; Astrothrombus H.L. Clark, 1909; Astrotoma Lyman, 1875; Astrozona Döderlein, 1930; Conocladus H.L. Clark, 1909; Ophiocrene Bell, 1894; Ophiozeta Koehler, 1930; Schizostella A.H. Clark, 1952. Description ARM. Arm shape unbranched, or shape branched; length more than 4× disc diameter; covering with granules.Arm combs absent. Dorsal arm plate present.Accessory dorsal arm plate absent. Ventral arm plate present. Accessory ventral arm plate absent. Girdle of tiny hooks on the arms present (Gorgonocephalus caputmedusae (Linnaeus, 1758)) or absent in some genera. Spines all similar in shape. Arm spine cross section oval. The ratio of thickness of distal ⅓ of arm spine to maximum thickness (in a given crosssectional plane) 0.9–1. Arm spines flat; at proximal segments only on ventral side of arms; predominantly erect, standing perpendicular to arm axis. Longest arm spines between half and one segment long. Tentacle scales present; pores visible along the arm; slightly longer than wide; shorter than the spine nearby; cross section round. Position of lateral arm plate (LAP) only lateral. Dorsal and/or ventral edge(s) of LAPs without constriction. Ventral position of LAP projecting ventro-proximalwards. Ventro-distal tip of LAP not projecting ventralwards. Arm spine articulation without dorsal and ventral lobes; restricted to (the ventral or central) portion of the distal edge; all similar. Distance between spine articulations ventralwards increasing. Nerve and muscle openings separated by large, prominent ridge or regular stereom. Nerve opening smaller than muscle opening. DORSAL DISC. Disc circular; flat (about same level as arms). Integument obscuring plates. Dorsal disc with granules; with concealed primary plates; with scales; without spines. Dorsal disc scale/plate without tubercles. Radial shield present; with/without granules; length more than half of the disc radius; bar-like. VENTRAL DISC. Gonads restricted to the disc. Ventral interradii with granules. Scales on ventral interradii absent. Ventral teeth several (tooth papillae). Infradental papillae on oral plate absent. Buccal scales on OP absent. Accessory oral papillae on OP present. Lateral oral papillae on OP absent.Adoral shield spine absent. Lyman’s ossicle absent. Oral shield covering less than one third of interradius; much wider than long. Madreporite one; with numerous pores. Adoral shield meeting in front of the oral shield. Abradial genital plate not twisted. Number of genital slits one per bursa. Genital slit shorter than half interradius. Genital papillae absent. Dental plate of equal width all over; fragmented. Dental sockets circular; equal to or more than 50% of the width. At least one socket on DP as depression or perforation without septum. Teeth spine-shaped. Teeth on DP arranged as covering the entire dental plate evenly. VERTEBRAE. Vertebrae hourglass-shaped (streptospondylous); beyond segment 5 with short keel; without oral bridge., Published as part of Goharimanesh, Mona, Stöhr, Sabine, Mirshamsi, Omid, Ghassemzadeh, Fereshteh & Adriaens, Dominique, 2021, Interactive identification key to all brittle star families (Echinodermata; Ophiuroidea) leads to revised morphological descriptions, pp. 1-63 in European Journal of Taxonomy 766 (1) on pages 21-22, DOI: 10.5852/ejt.2021.766.1483, http://zenodo.org/record/5514587, {"references":["Matsumoto H. 1915. A new classification of the Ophiuroidea: with descriptions of new genera and species. Proceedings of the Academy of Natural Sciences, Philadelphia 67: 43 - 92."]}

Ophiuroidea is the largest class among extant echinoderms, with over 2000 described species assigned to 33 families. Here, the first identification key to the recently revised classification was developed, and revised morphological descriptions were derived from it, expanding the previous short diagnoses. The key was built by analyzing internal and external skeletal characters of predominantly the type species of each family, including at least two mutually exclusive attributes per family. Various numeric and multistate characters were used to create a traditional as well as an interactive key using the DELTA and Xper software programs­. Illustrations (SEM and digital photos) are included in the key to facilitate the assessment of character states by users. Not only is it the first identification key to the families, according to the recently proposed new classification and the examined species, but this interactive key also assists users in understanding the family level taxonomy of brittle stars. The interactive key allows new characters and states to be added, when more species will have been analyzed, without the need to reconfigure the complete key (as may be necessary with conventional keys).

The first morphological observation of a euryalid brittle star, Asteronyx loveni, using non-destructive X-ray micro-computed tomography (µCT) was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5–15.4 µm) was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid's body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.

Published records on the Ophiuroidea fauna of the Persian Gulf and Gulf of Oman are scattered in difficult to access journals and books. This study presents a compilation of all published records, complemented with data from new samples. Distribution, habitat and depth in the study area, as well as known Indian Ocean distributions, are included. The taxonomic status of all species was evaluated, critical comments were added as applicable, and several previous records were reassigned to other species. Ophiocoma erinaceus was removed from the fauna of the Persian Gulf and Gulf of Oman, because the only published record was instead Ophiocoma schoenleinii. Previous studies assumed that 46 species of brittle star were known from the study area, but only 38 species were confirmed by this re-assessment, including two new records (Ophiothrix (Ophiothrix) foveolata and Ophiocomella sexradia). Diagnostic features are supplied for difficult to distinguish species. Five species (Macrophiothrix elongata, Amphiura fasciata, Amphiura (Ophiopeltis) hexactis, Amphioplus echinulatus, and Amphioplus seminudus) are so far worldwide known only from the Persian Gulf area. A hexamerous, fissiparous species of Ophiothela that does not concur with any known species was found and may represent a new species. All newly collected species are illustrated with photographs.

Astroboa nuda (Lyman, 1874) Astrophyton nudum Lyman, 1874: 251, pl. 6, figs 4, 5. Astroboa nuda — Döderlein 1911: 86–88. Habitat: Shells and gravel, 33 m (Mortensen 1940). Persian Gulf and Gulf of Oman: Bahrain (ibid.). Indian Ocean: Tanzania and Gulf of Aqaba (Tsurnamal & Marder 1966), Red Sea (Clark & Rowe 1971), Mozambique (Clark & Courtman-Stock 1976), Madagascar (Cherbonnier & Guille 1978), South Africa (Olbers et al. 2015, 2019), Réunion (Boissin et al. 2016)., Published as part of Fatemi, Yaser & Stöhr, Sabine, 2019, Annotated species list of Ophiuroidea (Echinodermata) from the Persian Gulf and Gulf of Oman, with new records, pp. 77-106 in Zootaxa 4711 (1) on page 82, DOI: 10.11646/zootaxa.4711.1.3, http://zenodo.org/record/3573466, {"references":["Lyman, T. (1874) Ophiuridae and Astrophytidae, new and old. Bulletin of the Museum of Comparative Zoology at Harvard College, Cambridge, 3, 221 - 272. Available from: https: // biodiversitylibrary. org / page / 6705490 (Accessed 12 Dec. 2019)","Doderlein, L. (1911) Uber japanische und andere Euryalae. Abhandlungen der math. phys. Klasse der K. Bayer Akademie der Wissenschaften, 5, 1 - 123, pls. 1 - 9. https: // doi. org / 10.5962 / bhl. title. 16334","Mortensen, T. (1940) Echinoderms from the Iranian Gulf. Asteroidea, Ophiuroidea, and Echinoidea. Danish Scientific Investigations in Iran, Part 2, 55 - 112.","Tsurnamal, M. & Marder, J. (1966) Observations on the basket star Astroboa nuda (Lyman) on coral reefs as Elat (Gulf of Aqaba). Israel Journal of Ecology and Evolution, 15, 9 - 17. https: // doi. org / 10.1080 / 00212210.1966.10688225","Clark, A. M. & Rowe, F. W. E. (1971) Monograph of Shallow-water Indo-west Pacific Echinoderms. Trustees of the British Museum (Natural History), London, 234 pp.","Clark, A. M. & Courtman-Stock, J. (1976) The echinoderms of Southern Africa. British Museum, London, 277 pp.","Cherbonnier, G. & Guille, A. (1978) 48 Echinodermes: Ophiurides. Centre National de la Recherche Scientifique, Paris, 272 pp.","Olbers, J. M., Samyn, Y. & Griffiths, C. L. (2015) New or notable records of brittle stars (Echinodermata: Ophiuroidea) from South Africa. African Natural History, 11, 83 - 116. https: // doi. org / 10.17159 / 2305 - 7963 / 2015 / v 11 n 1 a 3","Olbers, J. M., Griffiths, C. L., O'Hara, T. D. & Samyn, Y. (2019) Field guide to the brittle and basket stars (Echinodermata: Ophiuroidea) of South Africa. ABCTaxa. Vol. 19. Belgian National Focal Point to the Global Taxonomy Initiative, Brussels, 346 pp.","Boissin, E., Hoareau, T. B., Paulay, G. & Bruggemann, J. H. (2016) Shallow-water reef ophiuroids (Echinodermata: Ophiuroidea) of Reunion (Mascarene Islands), with biogeographic considerations. Zootaxa, 4098 (2), 273 - 297. https: // doi. org / 10.11646 / zootaxa. 4098.2.4"]}

Astrodia tenuispina (Verrill, 1884) Reports for the Azores: Astrodia tenuispina (Verrill, 1884) — $ Sibuet 1972: 121–122; Pérès 1992: 254. Type locality: off Nantucket Shoals. See: Verrill (1884: 219, as Asteronyx tenuispina); Okanishi & Fujita (2014: 198–200, figs. 10–11). Occurrence: cosmopolitan, in the Pacific and Atlantic Oceans; in the Atlantic, from off Nantucket Island to Brazil including the Caribbean and Gulf of Mexico deep waters, eastwards from Rockall Trough south to the Iberian Peninsula, including the Canary Islands and the Azores (Sibuet 1972; Okanishi & Fujita 2014). Depth: 512– 3,548 m (Okanishi & Fujita 2014); AZO: 2,480 m (Sibuet 1972). Habitat: epizooic on other sedentary marine species, such as the pennatulid Scleroptilum grandiflorum K̂lliker, 1880 on which the Azorean specimen was found (Sibuet 1972); probably planktivorous (Gage et al. 1983). Larval stage: produces large yolky eggs, possibly indicative of a direct or lecithotrophic development (Gage et al. 1983). Remarks: the record of the cosmopolitan Astrodia tenuispina in the archipelago was based on a single specimen collected by bathyscaphe Archimède in 1969, north of S„o Miguel Island, and later identified by Sibuet (1972). See also remarks below, under Asteroschema inornatum Koehler, 1906a., Published as part of Madeira, Patrícia, Kroh, Andreas, Cordeiro, Ricardo, De, António M., Martins, Frias & Ávila, Sérgio P., 2019, The Echinoderm Fauna of the Azores (NE Atlantic Ocean), pp. 1-231 in Zootaxa 4639 (1) on pages 31-32, DOI: 10.11646/zootaxa.4639.1, http://zenodo.org/record/3342161, {"references":["Verrill, A. E. (1884) Notice of the remarkable marine fauna occupying the outer banks off the southern coast of New England. American Journal of Science, 28, 213 - 220. https: // doi. org / 10.2475 / ajs. s 3 - 28.165.213","Sibuet, M. (1972) Echinodermes recoltes lors de la mission du Bathyscaphe Archimede aux Acores en 1969. Publications du Centre national pour l'exploitation des oceians. Reisultats des campagnes aI la mer, 3, 121 - 123.","Peres, J. M. (1992) Le bathyscaphe francais Archimede aux Acores: etude bionomique et ecologique du benthos profond. Acoreana, Suplemento, 237 - 264.","Okanishi, M. & Fujita, T. (2014) A taxonomic review of the genus Astrodia (Echinodermata: Ophiuroidea: Asteronychidae). Journal of the Marine Biological Association of the United Kingdom, 94, 187 - 201. https: // doi. org / 10.1017 / S 0025315413001331","K ˆ lliker, A. von (1880) Report on the Pennatulida dredged by H. M. S. Challenger during the years 1873 - 1876. Reports of Science Research Voyage of H. M. S. Challenger, Zoology, 1 (2), 1 - 41.","Gage, J. D., Billett, D. S. M., Jensen, M. & Tyler, P. A. (1983) Echinoderms of the Rockall Trough and adjacent areas. I. Crinoidea, Asteroidea and Ophiuroidea. Bulletin of the British Museum (Natural History), Zoology, 45, 263 - 308. https: // doi. org / 10.5962 / bhl. part. 28002","Koehler, R. (1906 a) Description des ophiures nouvelles recueillies par le Travailleur et le Talisman. Memoires de la Societe Zoologique de France, 19, 5 - 34."]}

Asteroschema inornatum Koehler, 1906a Reports for the Azores: Asteroschema inornatum Koehler, 1906 — $ Koehler 1909: 205, pl. 7, fig. 1, 1921a: 2; A.H. Clark 1948: 78; Paterson 1985: 16, fig. 10; García–Diez et al. 2005: 48; $ St̂hr & Segonzac 2005: 386; Martynov & Litvinova 2008: 78–79, fig. 1B; Smirnov et al. 2014: 194. Type locality: Bay of Biscay. See: Koehler (1906a: 30–31, pl. 3, figs. 45, 47; 1921a); Paterson (1985). Occurrence: North Atlantic deep waters, from off Nova Scotia and the Reykjanes Ridge (S of Iceland) on the Mid-Atlantic Ridge, south of the Charlie-Gibbs Fracture Zone to the Azores and from the Rockall Trough south of the Bay of Biscay to Madeira (Koehler 1921 a, Martynov & Litvinova 2008). Depth: 1,300 –2,300 m (St̂hr & Segonzac 2005, Martynov & Litvinova 2008); AZO: 1,478 –2,300 m (Koehler 1909, St̂hr & Segonzac 2005). Habitat: found in association with gorgonians (Gage et al. 1983). Remarks: Simroth (1888) reported a small young euryalid collected in the Azores. Only two species belonging to the order Euryalida are known from the archipelago, Astroschema inornatum and Astrodia tenuispina, both known from Azorean waters well below 1,000 m. Aside from the small size of the specimen, Simroth (1888) presented no further details and we have no knowledge where this animal could be housed. Nevertheless, Koehler (1909, 1921a) and more recently St̂hr & Segonzac (2005) collected material belonging to Asteroschema inornatum in the archipelago, thus confirming this species’ presence in the Azores., Published as part of Madeira, Patrícia, Kroh, Andreas, Cordeiro, Ricardo, De, António M., Martins, Frias & Ávila, Sérgio P., 2019, The Echinoderm Fauna of the Azores (NE Atlantic Ocean), pp. 1-231 in Zootaxa 4639 (1) on page 32, DOI: 10.11646/zootaxa.4639.1, http://zenodo.org/record/3342161, {"references":["Koehler, R. (1906 a) Description des ophiures nouvelles recueillies par le Travailleur et le Talisman. Memoires de la Societe Zoologique de France, 19, 5 - 34.","Koehler, R. (1909) Echinodermes provenant des campagnes du yacht Princesse-Alice (Asteries, Ophiures, Echinides et Crinoides). Resultats des campagnes scientifiques accomplies sur son yacht par Albert Ier Prince Souverain de Monaco, 34, 1 - 317.","Clark, A. H. (1948) Some interesting starfishes and brittle stars dredged by the Atlantis in mid-Atlantic. Journal of The Washington Academy of Sciences, 38, 75 - 78.","Paterson, G. L. J. (1985) The deep-sea Ophiuroidea of the North Atlantic Ocean. Bulletin of the British Museum (Natural History), Zoology Series, 49 (1), 1 - 162.","Garcia-Diez, C., Porteiro, F. M., Meirinho, A., Cardigos, F. & Tempera, F. (2005) Taxonomic review of selected invertebrate groups collected during the Campaigns of the Prince Albert I of Monaco in the Azorean waters. Arquipelago. Life and Marine Sciences, 22 A, 35 - 59.","St ˆ hr, S. & Segonzac, M. (2005) Deep-sea ophiuroids (Echinodermata) from reducing and non-reducing environments in the North Atlantic Ocean. Journal of the Marine Biological Association of the United Kingdom, 85 (2), 383 - 402. https: // doi. org / 10.1017 / S 0025315405011318 h","Martynov, A. V. & Litvinova, N. M. (2008) Deep-water Ophiuroidea of the northern Atlantic with descriptions of three new species and taxonomic remarks on certain genera and species. Marine Biology Research, 4, 76 - 11. https: // doi. org / 10.1080 / 17451000701840066","Smirnov, I. S., Piepenburg, D., Ahearn, C. & Juterzenka, K. V. (2014) Deep-sea fauna of European seas: An annotated species check-list of benthic invertebrates living deeper than 2000 m in the seas bordering Europe. Ophiuroidea. Invertebrate Zoology, 11 (1), 192 - 209. https: // doi. org / 10.15298 / invertzool. 11.1.18","Koehler, R. (1921 a) Echinodermes (Asteries, Ophiures, Echinides et Crinoides) des dernieres campagnes de la Princesse-Alice et de l' Hirondelle II. Bulletin de l'Institut Oceanographique de Monaco, 396, 1 - 8.","Gage, J. D., Billett, D. S. M., Jensen, M. & Tyler, P. A. (1983) Echinoderms of the Rockall Trough and adjacent areas. I. Crinoidea, Asteroidea and Ophiuroidea. Bulletin of the British Museum (Natural History), Zoology, 45, 263 - 308. https: // doi. org / 10.5962 / bhl. part. 28002","Simroth, H. (1888) Zur kenntnis der Azorenfauna. Archiv f ̡ r Naturgeschichte, Berlin, 54 (1), 179 - 234."]}

Madeira, Patrícia, Kroh, Andreas, Cordeiro, Ricardo, De, António M., Martins, Frias, Ávila, Sérgio P. (2019): The Echinoderm Fauna of the Azores (NE Atlantic Ocean). Zootaxa 4639 (1): 1-231, DOI: https://doi.org/10.11646/zootaxa.4639.1

Family Gorgonocephalidae Ljungman, 1867 Astrochelidae Verrill, 1899a: 79. Type genus Gorgonocephalus Leach, 1815 (type species: G. caputmedusae (Linnaeus, 1758)). Other genera Asteroporpa Örstedt & Lütken, 1856, Astracme Döderlein, 1927, Astroboa Döderlein, 1911, Astrocaneum Döderlein, 1911, Astrochalcis Koehler, 1905, Astrochele Verrill, 1878, Astrochlamys Koehler, 1912, Astrocladus Verrill, 1899b, Astroclon Lyman, 1879, Astrocnida Lyman, 1872, Astrocrius Döderlein, 1927, Astrocyclus Döderlein, 1911, Astrodendrum Döderlein, 1911, Astrodictyum Döderlein, 1927, Astroglymma Döderlein, 1927, Astrogomphus Lyman, 1869, Astrogordius Döderlein, 1911, Astrohamma Döderlein, 1930, Astrohelix Döderlein, 1930, Astroniwa McKnight, 2000, Astrophyton Fleming, 1828, Astroplegma Döderlein, 1927, Astrosierra Baker, 1980, Astrospartus Döderlein, 1911, Astrothamnus Matsumoto, 1915, Astrothorax Döderlein, 1911, Astrothrombus H.L. Clark, 1909a, Astrotoma Lyman, 1875, Astrozona Döderlein, 1930, Conocladus H.L. Clark, 1909b, Ophiocrene Bell, 1894, Ophiozeta Koehler, 1930, Schizostella A.H. Clark, 1952. Diagnosis Dorsal disc and arms with scales and plates, which bear thorny granules or spines. Girdles of small hyaline hooks on the arms. Arms branching or simple. All vertebrae without oral bridge. Gonads restricted to disc. Multiple teeth in irregular columns, dental plate entire. Arm spine articulation with slit-shaped muscle opening proximally bordered by vertical ridge, small nerve opening at a distance., Published as part of Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben & Martynov, Alexander, 2018, Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification, pp. 1-35 in European Journal of Taxonomy 416 on page 7, DOI: 10.5852/ejt.2018.416, http://zenodo.org/record/3806109, {"references":["Ljungman A. V. 1867. Ophiuroidea viventia huc usque cognita. Ofversigt af Kungliga Vetenskaps- Akademiens Forhandlingar 1866 23: 303 - 336.","Verrill A. E. 1899 a. Report on the Ophiuroidea collected by the Bahama expedition in 1893. Bulletin from the Laboratories of Natural History of the State University of Iowa 5: 1 - 86.","Linnaeus C. 1758. Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, 10 th edn. Holmiae, Stockholm.","Lutken C. F. 1856. Bidrag til kundskab om Slangestjernerne. II. Oversigt over de vestindiske Ophiurer. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i KjObenhavn 1856 8: 1 - 19.","Doderlein L. 1927. Indopacifische Euryale. Abhandlungen der Bayerische Akademie der Wissenschaften 31: 1 - 105, pls 1 - 10.","Doderlein L. 1911. Uber japanische und andere Euryalae. Abhandlungen der math. phys. Klasse der KOniglichen Bayerischen Akademie der Wissenschaften 5: 1 - 123, pls 1 - 9.","Koehler R. 1905. Ophiures littorales. Siboga Expeditie Monographs 45 b: 1 - 140, pls. 1 - 18.","Verrill A. E. 1878. Notice of recent additions to the marine fauna of the eastern coast of North America. Nos. 1 & 2. American Journal of Science 16: 207 - 215.","Koehler R. 1912. Echinodermes (Asteries, Ophiures et Echinides). In: (eds) Deuxieme Expedition Antarctique Francaise (1908 - 1910) commande par le Dr Jean Charcot: 272, 16 pls. Masson, Paris.","Verrill A. E. 1899 b. North American Ophiuroidea. I. - Revision of certain families and genera of West Indian Ophiurans. II. - A faunal catalogue of the known species of West Indian Ophiurans. Transactions of the Connecticut Academy 10: 301 - 386.","Lyman T. 1879. Ophiuridae and Astrophytidae of the \" Challenger \" expedition. Part II. Bulletin of the Museum of Comparative Zoology at Harvard 6: 17 - 83.","Lyman T. 1872. Note sur les Ophiurides et Euryales qui se trouvant les collections de Museum d'Histoire Naturelle de Paris. Annales des Sciences Naturelles, series 5, Zoologie 16: 1 - 8.","Lyman T. 1869. Preliminary report on the Ophiuridae and Astrophytidae dredged in deep water between Cuba and Florida Reef. Bulletin of the Museum of Comparative Zoology 1: 309 - 354.","Doderlein L. 1930. 2. Euryale. In: Die Ophiuroiden der Deutschen Tiefsee-Expedition. Wissenschaftliche Ergebnisse der Deutschen Tiefsee-Expedition auf dem Dampfer \" Valdivia \" 1898 - 1899: 348 - 396, pls 14 - 16.","McKnight D. G. 2000. The Marine Fauna of New Zealand: Basket-stars and Snake-stars (Echinodermata: Ophiuroidea: Euryalinida). National Institute of Water and Atmospheric Research, Auckland, New Zealand.","Fleming J. 1828. An History of British Animals Exhibiting their Descriptive Characters and Systematical Arrangement of Genera and Species of Quadrupeds, Birds, Reptiles, Fishes, Mollusca, and Radiata of the United Kingdom. Bell & Bradfute, Edinburgh.","Baker A. N. 1980. Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the southwest Pacific Ocean. New Zealand Journal of Zoology 7: 11 - 83.","Matsumoto H. 1915. A new classification of the Ophiuroidea: with descriptions of new genera and species. Proceedings of the Academy of Natural Sciences, Philadelphia 67: 43 - 92.","Clark H. L. 1909 a. Scientific results of the trawling expedition of H. M. C. S. \" Thetis \" off the coast of New South Wales, in February and March 1898. Echinodermata. Memoirs of the Australian Museum 4: 519 - 564.","Lyman T. 1875. Zoological results of the Hassler Expedition. 2. Ophiuridae and Astrophytidae. Illustrated catalogue of the Museum of Comparative Zoology at Harvard College 8: 1 - 34, 5 pls.","Clark H. L. 1909 b. Notes on some Australian and Indo-Pacific echinoderms. Bulletin of the Museum of Comparative Zoology at Harvard University 52: 109 - 135.","Bell F. J. 1894. On the echinoderms collected during the voyage of H. M. S. Penguin and by H. M. S. Egeria, when surveying Macclesfield Bank. Proceedings of the Zoological Society of London, 1894: 392 - 413.","Koehler R. 1930. Ophiures recueillies par le Docteur Th. Mortensen dans les Mers d'Australie et dans l'Archipel Malais. Papers from Dr. Th. Mortensen's Pacific Expedition 1914 - 16. LIV. Videnskabelige Meddelelser fra Dansk naturhistorisk Forening 89: 1 - 295.","Clark A. H. 1952. Schizostella, a new genus of brittle-star (Gorgonocephalidae). Proceedings of the United States National Museum 102: 451 - 454, plate 40. https: // doi. org / 10.5479 / si. 00963801.102 - 3307.451"]}

Order Euryalida Lamarck, 1816 Diagnosis Arm spine articulations with muscle and nerve openings well separated. Arm spines ventral only. Lateral arm plates devoid of ornamentation. Vertebrae with hourglass-shaped articulations., Published as part of Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben & Martynov, Alexander, 2018, Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification, pp. 1-35 in European Journal of Taxonomy 416 on page 6, DOI: 10.5852/ejt.2018.416, http://zenodo.org/record/3806109, {"references":["Lamarck J. B. de 1816. Histoire naturelle des animaux sans vertebres. L'Imprimerie d'Abel Lanoe, Paris."]}

Family Euryalidae Gray, 1840 Type genus Euryale Lamarck, 1816 (type species: E. aspera Lamarck, 1816). Other genera Asteromorpha Lütken, 1869, Asteroschema Örstedt & Lütken, 1856, Asterostegus Mortensen, 1933 a, Astrobrachion Döderlein, 1927, Astroceras Lyman, 1879, Astrocharis Koehler, 1904, Ophiocreas Lyman, 1869, Squamophis Okanishi et al. 2011, Sthenocephalus Koehler, 1898, Trichaster Agassiz, 1836. Diagnosis Dorsal disc with thickened skin and embedded external ossicles. Single column of teeth, dental plate fragmented. Arms branching in Euryale, Trichaster and Sthenocephalus. Distal vertebrae with oral bridge in Asteromorpha, Asterostegus, Astrobrachion, Astroceras, Euryale, Sthenocephalus and Trichaster (Okanishi et al. 2011 b). Gonads may extend into the arms. Arm spine articulation with large muscle opening separated from the nerve opening by a large, swollen ridge., Published as part of Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben & Martynov, Alexander, 2018, Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification, pp. 1-35 in European Journal of Taxonomy 416 on page 7, DOI: 10.5852/ejt.2018.416, http://zenodo.org/record/3806109, {"references":["Gray J. E. 1840. Room II. In: Synopsis of the contents of the British Museum: 57 - 65. British Museum, London.","Lamarck J. B. de 1816. Histoire naturelle des animaux sans vertebres. L'Imprimerie d'Abel Lanoe, Paris.","Lutken C. F. 1869. Additamenta ad historiam Ophiuridarum. 3. Beskrivende og kritiske Bidrag til Kundskab om Slangestjernerne. Det kongelige danske Videnskabernes Selskabs Skrifter 5: 24 - 109.","Lutken C. F. 1856. Bidrag til kundskab om Slangestjernerne. II. Oversigt over de vestindiske Ophiurer. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i KjObenhavn 1856 8: 1 - 19.","Mortensen T. 1933. Echinoderms of South Africa (Asteroidea and Ophiuroidea). Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening 93: 215 - 400.","Doderlein L. 1927. Indopacifische Euryale. Abhandlungen der Bayerische Akademie der Wissenschaften 31: 1 - 105, pls 1 - 10.","Lyman T. 1879. Ophiuridae and Astrophytidae of the \" Challenger \" expedition. Part II. Bulletin of the Museum of Comparative Zoology at Harvard 6: 17 - 83.","Koehler R. 1904. Ophiures de mer profonde. Siboga Expeditie Monographs 45 a: 1 - 176, pls 1 - 36.","Lyman T. 1869. Preliminary report on the Ophiuridae and Astrophytidae dredged in deep water between Cuba and Florida Reef. Bulletin of the Museum of Comparative Zoology 1: 309 - 354.","Okanishi M., O'Hara T. D. & Fujita T. 2011. A new genus Squamophis of Asteroschematidae (Echinodermata: Ophiuroidea: Euryalida) from Australia. Zookeys 129: 1 - 15. https: // doi. org / 10.3897 / zookeys. 129.1202","Koehler R. 1898. Echinodermes, receuillis par l'Investigator dans l'Ocean Indien. II. Les ophiures littorales. Bulletin Scientique de la France et de la Belgique 31: 55 - 124.","Agassiz L. 1836. Prodrome d'une monographie des radiaires ou Echinodermes. Memoires de la Societe des Sciences Naturelle de Neuchatel 1: 168 - 199."]}

Family Asteronychidae Ljungman, 1867 Type genus Asteronyx Müller & Troschel, 1842 (type species: A. loveni Müller & Troschel, 1842). Other genera Astrodia Verrill, 1899b, Astronebris Downey, 1967, Ophioschiza H.L. Clark, 1911. Diagnosis Dorsal disc with thickened skin, few or no scales, radial shields bar-like, almost meeting in disc centre. Long, tapering arms, covered by thickened skin, lacking dorsal plates. Multiple columns of spiniform teeth, dental plate entire. Arms not branching. All vertebrae without oral bridge. Gonads restricted to disc. Arm spine articulation as slightly tumid regular stereom with large oval or round opening., Published as part of Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben & Martynov, Alexander, 2018, Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification, pp. 1-35 in European Journal of Taxonomy 416 on pages 6-7, DOI: 10.5852/ejt.2018.416, http://zenodo.org/record/3806109, {"references":["Ljungman A. V. 1867. Ophiuroidea viventia huc usque cognita. Ofversigt af Kungliga Vetenskaps- Akademiens Forhandlingar 1866 23: 303 - 336.","Muller J. H. & Troschel F. H. 1842. System der Asteriden. Vieweg & Sohn, Braunschweig.","Verrill A. E. 1899 b. North American Ophiuroidea. I. - Revision of certain families and genera of West Indian Ophiurans. II. - A faunal catalogue of the known species of West Indian Ophiurans. Transactions of the Connecticut Academy 10: 301 - 386.","Downey M. E. 1967. Astronebris tatafilius (Euryale: Asteronychidae), a new genus and species of ophiuroid from the Aleutians, with a revised key to the family Asteronychidae. Proceedings of the Biological Society of Washington 80: 41 - 46.","Clark H. L. 1911. North Pacific Ophiurans in the collection of the United States National Museum. Smithsonian Institution United States National Museum Bulletin 75: 1 - 302."]}

Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben, Martynov, Alexander (2018): Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification. European Journal of Taxonomy 416: 1-35, DOI: https://doi.org/10.5852/ejt.2018.416

A revision of the genus Astrodendrum Döderlein (Ophiuroidea, Euryalida, Gorgonocephalidae) is based on 14 specimens, including the holotypes of Astrodendrum galapagense A. H. Clark and Astroconus capense Mortensen and a syntype of Gorgonocephalus sagaminus Döderlein. A new species Astrodendrum spinulosum is described from the Pacific coast of Japan. It is distinguished from its congeners in having conical external ossicles on aboral side of the disc; bulges on lateral edges of proximal arms; 1 terminal projection on each arm spine of proximal portion of the arm; 2 or 3 secondary teeth on each hook-shaped arm spine of distal portion of the arm. A taxonomic key to all six species of the genus Astrodendrum is provided.

Astrodendrum spinulosum sp. nov. (Figs 2–7) [Japanese Name: Toge-Tsuruboso-Tezurumozuru] Astrodendrum sagaminum — Irimura, 1982. 79, text fig. 4, pl. 2, figs 4–5. (Non Astrodendrum sagaminum Döderlein, 1911. 38– 39, pl. 2 figs 3–5, pl. 7, fig. 8) Type materials. NSMT E-6237, holotype, collected by fishery boat Taku-Maru, off Ohakozaki, Otsuchi, Iwate Prefecture, northeastern Japan, 39˚21.N, 142˚00.E, 75 m depth, 9 May 2008 (Type locality). NSMT E-10715, one paratype, collected by T/ S Seisui-Maru, off Shima Peninsula, Mie Prefecture, central Japan, 34˚11.42’N, 136˚41.54’E, 111 m depth, 12 October 2016. NSMT E-6905, one paratype, collected by R/ V Yayoi, off Ohakozaki, off Otsuchi, Iwate Prefecture, northeastern Japan, 39˚25.48’N, 135˚58.44’E, 78.2 m depth, 28 April 2009. NSMT E-10716, one paratype, collected by R/ V Yayoi, off Ohakozaki, Otsuchi, Iwate Prefecture, northeastern Japan, 39˚21.32’N, 142˚00.23’E-39˚21.28’N, 142˚00.28’E, 73–86 m depth, 27 June 2016 (Fig. 1). Other material. NSMT-Oph R: 22, one specimen, off Hayama, Sagami Bay, Kanagawa Prefecture, central Japan, 90–108 m depth, 22 November, 1930. NSMT-Oph R: 25, one specimen and NSMT-Oph R: 26, one specimen, 3.2 km off south Enoshima Island, Kanagawa Prefecture, central Japan, 144 m depth, 11 August 1935. NSMT-Oph R: 27, one specimen, Minami Amadaiba, Sagami Bay, Kanagawa Prefecture, central Japan, 200 m depth, 27 August 1935. NSMT-Oph R: 43, one specimen, off Hayama, Sagami Bay, Kanagawa Prefecture, central Japan, depth unknown, 14 February 1950. NSMT-Oph R: 73, one specimen, near Kodane, Kanagawa Prefecture, central Japan, depth unknown, 6 December 1957. NSMT-Oph R: 75, Goromba, Sagami Bay, Kanagawa Prefecture, central Japan, 100–110 depth, 21 January 1958 (Fig. 1). Diagnosis. External ossicles on aboral and interradial lateral disc conical, separated; external ossicles on oral disc plate-shaped, fully in contact; bulges on lateral edges of proximal portion of the arm; terminal projection on each arm spine on proximal portion of the arm single or lacking; 0 to 3 secondary teeth on each hook-shaped arm spine on distal portion of the arm. Description of holotype. Disc. Disc five-lobed with notched interradial edges, 53 mm in disc diameter (Fig. 2). Radial shields and surrounding plates tumid (Figs 2A, 3A). Aboral disc covered by conical external ossicles (Fig. 3A–C). At periphery of the disc, ossicles separated and scattered, approximately 200 µm in length and 250 µm in height on radial shield (Fig. 3B), approximately 100–200 µm in length and 200 µm in height in interradii (Fig. 3B), and approximately 200 µm in length and 150–200 µm in height at center of disc (Fig. 3A, C). Radial shields completely concealed by external ossicles, bar-like, approximately 28 mm in length, 2.5 mm in width proximally and the width gradually increasing to 6 mm distally, but shields do not reach disc center (Fig. 3A). The oral surface of disc covered by polygonal plate-shaped external ossicles, fully in contact, approximately 200–250 µm in length. Oral shields, adoral shields, oral plates and ventral arm plates completely concealed by external ossicles (Fig. 3E). Teeth uniformly spiniform, situated on the top of dental plates and edges of oral plates (Fig. 3H). Teeth arranged in 1 or 2 transverse rows on oral plates, 8 to 10 in number (Fig. 3E), in a cluster covering oral-most part of dental plate, 7 to 10 in number (Fig. 3E), and in a vertical line, on other part of dental plates, 3 or 4 in number. Teeth varying in position and in size, approximately 2–3 mm in length, 0.7 mm in greatest width on dental plates, and 2 mm in length, 0.6–0.7 mm in width on oral plates (Fig. 3E). Interradial surface of lateral disc covered by conical external ossicles and skin (Figs 2B; 3H). Conical external ossicles, separated and scattered, approximately 100 µm in length and height (Fig. 3H). Ossicles increasing their height toward aboral side, reaching 500 µm (Fig. 3H). Ossicles fully in contact, approximately 200 µm in length and 0.8–1 mm in height on adradial edge of interradial lateral disc (Fig. 3H). Two genital slits (8 mm long and 1 mm wide) in each interradius (Fig. 3G). Spinule ossicles along the adradial edge of genital slits, 200 µm in length and 500 µm in height (Fig. 3G). One large, elliptical madreporite situated on oral interradius, approximately 5.4 mm in width and 3 mm in length (Fig. 3F). Arms. Arms branching. On the proximal portion of arm, before first branch, arm 11.0 mm wide and 6.2 mm high, with an arched aboral surface and flattened oral surface. Between first branch and second branch, arm width and height abruptly decreasing to 5.5 mm in width and 5.7 mm in height. Subsequently, arms tapering gradually toward arm tip (Fig. 4). On aboral and lateral surface, each arm segment covered by single annular row of large oblong plates, approximately 600–700 µm in transverse length (Fig. 3D). Before third branch, each plate separated by granular external ossicles. Plates fully in contact from fourth branch and subsequent distal segments (Fig. 4B). Before first branch, plates bearing no hooklets (Fig. 3D), after second branch, plates bearing hooklets (Fig. 4B). With exception of hooklet-bearing plates, aboral and lateral surface of arm completely covered by domed and polygonal granular external ossicles, fully in contact, approximately 200 µm in length (Fig. 3D). Before first branch, oral surface covered by polygonal and plate-shaped external ossicles, similar to those on oral disc. After first branch, granular external ossicles, slightly in contact, approximately 100 µm in length (Fig. 4A). In middle portion of arm, aboral and lateral surface covered by domed and round granular external ossicles, slightly in contact, approximately 170– 200 µm in length (Fig. 4B). Oral surface covered in round granular external ossicles, slightly in contact, approximately 70–80 µm in length (Fig. 4C). Distally, aboral and lateral surface of arm covered by round granular external ossicles, slightly in contact, approximately 60–70 µm in length (Fig. 4D). Oral surface covered by flat and round plate-shaped external ossicles, slightly in contact or separated, approximately 50–60 µm in length. Lateral arm plates and ventral arm plates completely concealed by skin and external ossicles on entire arm (Fig. 4A, C, E). First to sixth tentacle pore with single arm spine; seventh pores occasionally with 1 arm spine, eighth and subsequent pore with 2 or 3 spines (Fig. 4A, C). Distally, the number of arm spines decrease gradually to 2 toward arm tip (Fig. 4E). Arm spines approximately one-third to one-fourth of length of corresponding arm segment, and covered by thin integument (Fig. 4A, C, E). Color. Oral surface of arms and aboral disc dark brown, while radial shields and remaining areas pale brown (Fig. 2). Darker spots present on midline of proximal position of the arms (Fig. 3B). Ossicle morphology of the holotype. External ossicles on aboral periphery of radial shields conical, approximately 150 µm in length and 200 µm in height (Fig. 5A, B). Hooklet-bearing plates with 5 or 6 tubercleshaped articulations for hooklets in proximal portion of the arm (Fig. 5C), approximately 15 articulations in middle portion (Fig. 5E) and 8 articulations in distal portion (Fig. 5H); articulations forming 2 parallel rows (Fig. 5C, E, H). Each hooklet with single inner tooth and reticular structure (Fig. 5D, F, I). Lateral arm plates long, bar-like, with straight distal edge and concave proximal edge (Figs 5J, K; 6A, B, D, E). On proximal portion of arm, lateral arm plates with perforations on aboral side and pairs of simple nerve and muscle openings on oral-external side (Fig. 5J) and on middle to distal portion of arms, two nerve openings beside dorsal lobe and 3 articulations for hooklets on oral surfaces (Fig. 6A, B, D, E). Arm spines in proximal portion of arm ovoid, with a small projection, approximately one-seventh length of the height of spine (Fig. 5L). In middle and distal portion, arm spines transformed into hooks with 2 or 3 inner teeth, respectively (Fig. 6C, F). Hook-shaped arm spines distinguished from hooklets on aboral and lateral surface of arm by lack of reticular structure (Figs 5D, F, I, L; 6C, F). All vertebrae with hourglass-shaped streptospondylous articulations (Figs 6G–I; Fig. 7A, D–F), and distal side of branching vertebra slightly wider than in non-branching vertebra and with 2 articulation surfaces (Figs 6I; 7F). Surfaces of lateral furrows smooth, with no special ornamentations (Figs 6J; 7B, G). Depressions for tube feet openings in distal part of oral-lateral side of vertebrae (Figs 6J, K; 7C, H). A pair of radial water canals opening on lateral side of vertebrae, near depression of tube feet in the proximal to middle position of arms (Figs 6K, 7C) and opening in distal part of the oral groove of vertebrae in distal portion of arms (Fig. 7H). Distribution. JAPAN. Off Iwate (type locality), Sagami Bay (Irimura, 1982), and off Mie. Depth ranges 75– 200 m. Etymology. The specific name is latin for “spinulose”, referring to numerous conical external ossicles on aboral disc of this new species. Remarks. Irimura (1982) referred to nine specimens of Astrodendrum collected in the Sagami Sea, central Japan as Astrodendrum sagaminum (Döderlein, 1911) which is known from the Indo-West Pacific (see also “Distribution of Astrodendrum sagaminum ” below). Irimura (1982) described external ossicles on the disc as “granules” and failed to mention detailed morphology of the oral surface of the proximal portion of the arms and of each arm spine (Irimura, 1982). We re-examined seven (NSMT-Oph R: 22, 25, 26, 27, 43, 73, 75) of the nine TABLE 1. Tabular characters key to the species of the genus Astrodendrum. Characters of A. laevigatum are referređ to from the original đescription by Koehler, 1897. "-̏ means no đata. Shapes, sizes anđ arrangements of external ossicles on the đisc Bulges of Maximum number of Maximum number of lateral terminal projections of Species seconđary teeth of Aboral surface Oral surface Interrađial lateral surface eđges of arm spine on proximal hook-shapeđ arm spine proximal arms portion of the arm A. spinulosum Plate-shapeđ, fully in Cone-shapeđ, separateđ Cone-shapeđ, separateđ Present 1 3 sp. nov. contact Granule-shapeđ, fully in contact; Plate-shapeđ, fully in A. capensis Plate-shapeđ, fully in Cone-shapeđ, separateđ on rađial contact; Absent 3 2 (Mortensen, 1933) contact shielđs cone-shapeđ, separateđ specimens from Sagami Bay observed by Irimura (1982) and they were certainly different from Astrodendrum sagaminum in having uniform sized conical external ossicles on their disc and conformed to the diagnosis of Astrodendrum spinulosum sp. nov. (see below for the detailed morphological characters). Therefore, Irimura (1982) specimens are here referred to the new species. This new species falls within Astrodendrum in having external ossicles on its disc, a madreporite on the inner edge of the interradial lateral disc, and in lacking calcareous plates on the lateral disc margin (Fell, 1960; McKnight, 2000). Our re-examination of the type material and comparison of Astrodendrum species revealed that Astrodendrum spinulosum sp. nov. can be distinguished from the five currently valid species by the external ossicles on the aboral disc which are conical, and separated (Fig. 3A–C). In contrast, in the other congeners, the ossicles are: smaller granular, fully in contact and larger conical and, separated in A. capense (Fig. 8E, F); plate-shaped at periphery and conical at center, both slightly in contact in A. galapagense (Fig. 10B, C); smaller granular, fully in contact and larger granular, separated in A. elingamita (Baker, 1974); and smaller and larger granular, both separated in A. sagaminum (Fig. 12A). External ossicles on the interradial lateral surface of the disc are conical and, separated in this new species (Fig. 3H), as in A. sagaminum (Fig. 12B, D). In contrast, those of A. capense (Fig. 11B) and A. elingamita (Baker, 1974) are composed of plate-shaped ossicles, fully in contact, and granular ossicles, that are separated. Those of A. galapagense are plate-shaped, slightly in contact (Fig. 9A). External ossicles on the oral surfaces of the disc of the new species, A. capense, A. elingamita and A. sagaminum are plate-shaped and fully in contact (Figs 8H; 12B; Baker, 1974) and those of A. galapagense are granular and separated (Fig. 10D). The disc of A. laevigatum is covered only by skin without external ossicles (Koehler, 1897, 1899). This new species possesses bulges on lateral edges of proximal portion of the arms (Fig. 4A), whereas bulges lack in other species of Astrodendrum (Figs 8D; 9G; 12B; Baker, 1974). The presence of bulges of A. laevigatum is unknown (Koehler, 1897, 1899). The maximum number of terminal projections of each arm spine of proximal portion of the arm is single in this new species (Fig. 5L) and in A. sagaminum (Döderlein, 1911). That of A. galapagense is 2 (Fig. 11E) and of A. capense and A. elingamita is 3 (Mortensen, 1933; Baker, 1974, 1980). The maximum number of secondary teeth of each hook-shaped arm spine in the distal portion of the arm of this new species is 3 (Fig. 6F), a character shared with A. elingamita (Baker, 1980). In A. capense and A. sagaminum there are 2 (Döderlein, 1911; Mortensen, 1933) and there is 1 in A. galapagense (A. H. Clark, 1916). The maximum number of terminal projections and of secondary teeth mentioned above is not provided in A. laevigatum (Koehler, 1897, 1899; Bomford, 1913). Based on our morphological observations of type specimens and study with the literature, we found that all six species of Astrodendrum can be morphologically distinguished using six morphological characteristics. A tabular key to species is provided in Table 1.

Genus Astrodendrum Döderlein, 1911 Astrodendrum Döderlein, 1911: 38;— Fell, 1960: 8. Baker, 1980: 16, 56. McKnight, 2000: 55. Type species: Gorgonocephalus sagaminus Döderlein, 1902. Included species. A. capense (Mortensen, 1933); A. elingamita Baker, 1974; A. galapagense A. H. Clark, 1916; A. laevigatum (Koehler, 1897); A. sagaminum (Döderlein, 1902); Astrodendrum spinulosum sp. nov. Diagnosis emended. Arms five, branching. Number of arm segments less than six before first branch. No rows of calcareous plates on edge of disc margin. One madreporite situated on innermost portion of interradial lateral disc. Hooklets on aboral arms with one secondary tooth. Disc covered by variously shaped external ossicles or lacking any ossicles. Remarks. Only external ossicles of the disc have been used as a taxonomic character for Astrodendrum in recent taxonomic papers (Baker, 1974, 1980; McKnight, 2000). However, up to now, shape, size and arrangement of the external ossicles have not been sufficiently described for any Astrodendrum species other than A. elingamita. In this paper, the re-examination of the type specimens of A. capense, A. galapagense and A. sagaminum revealed that these characters clearly distinguish these three species from A. elingamita. No type specimen of A. laevigatum was examined during this study due to missing information on its deposition. However, the original description of A. laevigatum mentioned that this species lacks any external ossicles on the disc. During study of the type specimens of A. capense, A. galapagense and A. sagaminum together with a comparison of previous descriptions of A. elingamita and A. laevigatum, we found three new taxonomic characters to distinguish these three species: i) absence/presence of bulges on lateral ridges of proximal portion of the arm; ii) number of terminal projections of arm spines on proximal portion of the arm; and iii) number of secondary teeth of hook-shaped arm spines on distal portion of the arm (see also Remarks of Astrodendrum spinulosum sp. nov.; Table 1). McKnight (2000) stated “the disc with granular external ossicles in various size” as a diagnostic character of the genus Astrodendrum. However, as mentioned above, A. laevigatum lacks any external ossicles and A. spinulosum sp. nov. has conical external ossicles on the disc (Koehler, 1897, 1899; see also Remarks on Astrodendrum spinulosum sp. nov.). Therefore, we amended this diagnostic character to “the disc covered by various shaped external ossicles or none at all”. External features of Astrodendrum laevigatum are distinctive in the genus, and this species should possibly be separated from the other congeners. However, we here refrain from establishing a new genus for this species because we have not observed any type specimens of A. laevigatum. To confirm exact taxonomic position of A. laevigatum, molecular phylogenetic study of Astrodendrum including A. laevigatum as well as observation of the type specimen are required. This genus is widely distributed in the western Indo-Pacific to Atlantic Ocean, in a depth of 40–1314 m (Fig. 1)., Published as part of Okanishi, Masanori & Fujita, Toshihiko, 2018, A taxonomic review of the genus Astrodendrum (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) with description of a new species from Japan, pp. 289-310 in Zootaxa 4392 (2) on pages 290-291, DOI: 10.11646/zootaxa.4392.2.4, http://zenodo.org/record/1195409, {"references":["Doderlein, L. (1911) Beitrage zur Naturgeschichte Ostasiens. Uber japanische und andere Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, II. Suppl. - Bd., 5, 1 - 123.","Fell, H. B. (1960) Synoptic keys to the genera of Ophiuroidea. Zoology Publications from Victoria University of Wellington, 26, 1 - 44.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","McKnight, D. G. (2000) The Marine Fauna of New Zealand: Basket-stars and snake-stars (Echinodermata: Ophiuroidea: Euryalinida). National Institute of Water and Atmospheric Research Biodiversity Memoir, 115, 1 - 79.","Doderlein, L. (1902) Japanische Euryaliden. Zoologishcer Anzeiger, 25, 320 - 326.","Mortensen, T. (1933) Echinoderms of South Africa (Asteroidea and Ophiuroidea) Papers from Dr. Th. Mortensen's Pacific Expedition 1914 - 16. Videnskabelige Meddelelser fra Dansk naturhistorisk Forening, 93 (65), 215 - 400.","Baker, A. N. (1974) New species of brittle-stars from New Zealand (Echinodermata: Ophiuroidea). Records of the Dominion Museum, 8 (15), 247 - 266.","Clark, A. H. (1916) On a new starfish and five new brittle-stars from the Galapagos Islands. Annals and Magazine of Natural History, Series 8, 18, 115 - 122. https: // doi. org / 10.1080 / 00222931608693831","Koehler, R. (1897) Echinodermes recueillis par \" l'Investigator \" dans l'Ocean Indien. I. Les Ophiures de mer profonde. Annales des Sciences Naturelles Zoologie, Series 8, 4, 277 - 372.","Koehler, R. (1899) An account of the deep-sea Ophiuroidea collected by the Royal Indian Marine Survey Ship Investigator. Echinodermata of the Indian Museum, Ophiuroidea, Calcutta, 76 pp."]}

Astrodendrum galapagense A. H. Clark, 1916 (Figs 10, 11) Astrodendrum galapagensis A. H. Clark, 1916. 117;���D��derlein, 1927. 93; Downey, 1969. 49. Type material. USNM 38581, holotype, collected by R/ V Albatross, between Santa Cruz and San Cristobal Islands, Galapagos Islands, Pacific Ocean, 00˚29.00���S, 89˚54.30���W, 717 m deep, 15 April 1888 (Fig. 1). Diagnosis. External ossicles on aboral disc plate-shaped on periphery and conical in center, slightly in contact or separated; external ossicles on oral disc granular, separated; external ossicles on interradial lateral disc plateshaped, slightly in contact; bulges of lateral edges of proximal portion of arms absent; 2 terminal projections on each arm spine in proximal portion of arm; single secondary tooth on each hook-shaped arm spine in distal portion of arm. Description of holotype. Disc. Disc five-lobed with notched interradial edges, 7.4 mm in disc diameter (Fig. 10A). Radial shields tumid (Fig. 10A, C). Aboral disc covered by skin embedding plate-shaped and conical external ossicles, both slightly in contact or separated (Fig. 10A). Plate-shaped external ossicles, approximately 140���400 ��m in length at periphery of disc (Fig. 10B, C). Conical external ossicles approximately 110���150 ��m in length at center of disc (Fig. 10B, C). Radial shields bar-like, covered by skin and external ossicles, approximately 3.5 mm in length, width 0.8 mm distally gradually decreasing to 0.5 mm proximally, shields, almost reaching disc center (Fig. 10A, B). Oral surface of disc covered by skin and granular external ossicles, separated and scattered, approximately 70���100 um in length (Fig. 10D���F). Oral shields triangular, 0.5 mm in length and height, adoral shields also triangular, 1.5 mm in length and 0.7 mm in height, oral plates long, bar-like, approximately 0.5 mm in length at outer end and 0.2 mm at inner end, and 1 mm in height (Fig. 10D). Ventral arm plates completely concealed by thick skin and external ossicles (Fig. 10D). Uniformly acute and spiniform teeth on dental plates, approximately 0.2���0.5 mm in length and 4 to 5 in number (Fig. 10E). One or 2 conical teeth on edge of each oral plate, approximately 0.1���0.2 mm in length (Fig. 10E). Interradial surface of lateral disc covered by granular external ossicles, slightly in contact, 50���150 um in length (Fig. 11A). Two genital slits (1.5 mm long and 0.2 mm wide) in each interradius, carrying no spinule ossicles along genital slit (Fig. 11A). Madreporite completely covered by skin and external ossicles and invisible in external view (Fig. 10D). Arms. Arms 5, branching at least 7 times, but further branches indeterminate because of entanglement of arms. The first branch occurs beyond disc (Fig. 10A). On proximal portion of arm, the width and height approximately equal, 1.2 mm, with a concaved aboral surface and flattened oral surface. Arms tapering gradually toward arm tip (Fig. 10B���D). Aboral and lateral surface covered by granular external ossicles, slightly in contact, approximately 160���400 um in length (Fig. 11B). On each arm segment, a row of hooklet-bearing plates, approximately 800 ��m in length on aboral and lateral sides (Fig. 11B). On middle portion of arm and subsequent distal segments, hookletbearing plates fully in contact with each other (Fig. 10C, D). Hooklets have single secondary tooth. Aboral and lateral surface devoid of external ossicles and covered only by skin (Fig. 10C, D). On proximal portion of arm, oral surface covered by granular external ossicles, separated and scattered, 30 ��m in length (Fig. 11E). From middle to distal segments, the ossicles and only skin covering present. Throughout the arm, lateral arm plates and ventral arm plates completely concealed by skin and external ossicles (Fig. 11E). The first to third tentacle pores with no arm spine; fourth and subsequent pores have 2 (rarely 3) arm spines. In middle to distal portion of arm, the number of arm spines consistently 2. Those on proximal portion of arm ovoid, with up to 2 terminal projections (Fig. 11E). Inner arm spines, approximately half length of corresponding arm segment and outer spines approximately three quarters of inner spines in length (Fig. 11E). Those of middle portion of arm cylindrical, carrying 2 acute terminal projections, both inner and outer spines almost the same length as corresponding arm segment. Those of distal portion of arms transforming into hook, carrying single secondary tooth. Inner spines approximately half length of corresponding arm segment, and outer spines approximately half length of outer spines (Fig. 11D). Color. Aboral surfaces uniformly brown, radial shields exceptionally white (Fig. 10A), oral surface uniformly white (Fig. 10D). Distribution. REPUBLIC OF ECUADOR. Between Santa Cruz and San Cristobal Islands, Galapagos Islands, 717 m depth (Fig. 1) (Type locality, A. H. Clark, 1916). Remarks. Astrodendrum galapagense can be distinguished from its congeners in having plate-shaped external ossicles, while the other five species lack plate-shaped ossicles on aboral surface of the disc. A. galapagense is unique in having a maximum of two terminal projections on the proximal portion of the arm; The number of projections is three in A. capense and A. elingamita, and 1 in A. sagaminum and A. spinulosum sp. nov. The maximum number of secondary teeth of hook-shaped external ossicles of distal portion of the arms of A. galapagense is one; A. capense and A. sagaminum have two, and A. elingamita and A. spinulosum have three (Table 1, see also remarks for A. spinulosum)., Published as part of Okanishi, Masanori & Fujita, Toshihiko, 2018, A taxonomic review of the genus Astrodendrum (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) with description of a new species from Japan, pp. 289-310 in Zootaxa 4392 (2) on pages 304-307, DOI: 10.11646/zootaxa.4392.2.4, http://zenodo.org/record/1195409, {"references":["Clark, A. H. (1916) On a new starfish and five new brittle-stars from the Galapagos Islands. Annals and Magazine of Natural History, Series 8, 18, 115 - 122. https: // doi. org / 10.1080 / 00222931608693831"]}

Astrodendrum sagaminum (Döderlein, 1902) (Figs 12) [Japanese Name: Tsuruboso-Tezurumozuru] Gorgonocephalus sagaminus Döderlein, 1902. 321–322;—H. L. Clark, 1911. 292–293; Jangoux et al., 1987. 308. Astrodendrum sagaminum Döderlein, 1911. 38–39, pl. 2 figs 3–5, pl. 7, fig. 8;—Döderlein, 1927. 32, 92; Bomford, 1913. 220; H. L. Clark, 1915. 185; Matsumoto, 1917. 73–74, fig. 21; Murakami, 1944. 247; Chang et al., 1962. 58–59, pl. 1, figs 3–4; Irimura, 1991. 120, 2 plates; Irimura & Kubodera, 1998. 138; Kroh, 2002. 148, 150–151, fig. 4–1. Type material. ZSM 448 /1, one syntype, collected by Haberer, Sagami Bay, Japan, 1900 (Fig. 1). Diagnosis. Two sizes (larger and smaller) and scattered granular external ossicles on interradial aboral disc; uniform-size and fully in contact granular and conical external ossicles on radial shields; external ossicles conical, separated on interradial lateral disc; external ossicles plate-shaped and granular, both fully in contact on oral disc; bulges of lateral edges of proximal portion of arms absent; single terminal projection on each arm spine of proximal portion of arm; 2 secondary teeth on each hook-shaped arm spine of distal portion of arm. Description of a syntype. Disc. Disc five-lobed with notched interradial edges, 20 mm disc diameter (Fig. 12A). Aborally, radial shields tumid (Figs 12A). On aboral disc, interradial spaces and spaces between each pair of radial shields entirely covered by different sizes (larger and smaller) of granular external ossicles, separated and scattered (Fig. 12A). Larger granular external ossicles approximately 150–200 µm in length, and smaller external ossicles approximately 50–100 µm in length (Fig. 12A). Radial shields covered by uniform-size external ossicles, fully in contact, approximately 100 µm in length (Fig. 12A), conical 100 µm high on distal edge of radial shields and granular in the other areas (Fig. 12A). Center of disc covered by larger granular external ossicles, approximately 250 µm and smaller granular external ossicles approximately 50–100 µm in length, both separated and scattered (Fig. 12A). Lateral edge of disc covered by uniform-size conical external ossicles, separated and scattered, approximately 100 µm in length and height (Fig. 12A). Radial shields completely concealed by external ossicles, bar-like, approximately 10 mm in length, 1.5 mm in width, and almost reaching disc center (Fig. 12A). Oral surface of disc covered by external ossicles, approximately 200–300 um in length (Fig. 12B), flat, polygonal and fully in contact on oral plate and slightly tumid, round and slightly in contact on adoral plates (Fig. 12A). Oral shields, adoral shields, oral plates and ventral arm plates completely concealed by external ossicles. Uniformly flat and spiniform teeth situated on the dental plates and edge of each oral plate, approximately 0.5–0.8 mm in length and approximately 20–25 in number on each jaw (Fig. 12B). Lateral surface of oral disc covered by conical external ossicles, separated and scattered, approximately 80–100 µm in length and height (Fig. 12B, D). Two genital slits (5 mm long and 1.5 mm wide) in each interradius (Fig. 12D). One elliptical madreporite situated on oral interradius, approximately 2.7 mm in length and 1.0 mm in height (Fig. 12B). Arms. Arms 5, branching at least 8 times but number of branches indeterminate because of entanglement of arms (Fig. 12C). The first branch occurs beyond disc (Fig. 12A, B). On the proximal portion of the arm, width and height almost equal, 4.5 mm in width. Arms with a concave aboral surface and flattened oral surface. Arms tapering gradually toward arm tip (Fig. 12C). On aboral and lateral surface of proximal portion of arm, each arm segment covered by granular external ossicles, fully in contact (Fig. 12C). On proximal portion of arms, granules 100–150 µm in length (Fig. 12A), gradually decreasing in size toward arm tip. Oral surface of proximal portion of arms covered by flat, polygonal plate-shaped external ossicles, similar to those on oral disc, approximately 200–300 µm in length (Fig. 12C). Before the first branches, the first to third tentacle pores with no arm spine; single arm spine at fourth pores (Fig. 12B), and subsequent pores with 2 or 3 arm spines (Fig. 12B). Color. Uniformly creamy white (Fig. 12). Distribution. JAPAN. Sagami Bay (type locality, Döderlein, 1902; 1911; Matsumoto, 1917; Irimura, 1982, 1991; Jangoux et al., 1987), off eastern Japan (H. L. Clark, 1915); Suruga Bay (H. L. Clark, 1911; Döderlein, 1927; Kroh, 2002); Ogasawara or Yaeyama Islands (Murakami, 1944: detailed locality is unknown). East China Sea (Irimura & Kubodera, 1998). CHINA. East China Sea (Chang et al., 1962). SRI LANKA. Southwest off Colombo (Bomford, 1913). Depth ranges 90–1300 m (Fig. 1). Remarks. Astrodendrum sagaminum shares with A. spinulosum sp. nov. the presence of conical external ossicles, that are, separated and scattered on interradial lateral disc, while those of A. capense, A. elingamita and A. galapagense are plate-shaped and/or granular. A. laevigatum lacks external ossicles on the disc. A. sagaminum and A. spinulosum sp. nov. can be distinguished by absence/presence of granular external ossicles on disc, absence/presence of bulges of lateral edges on the proximal portion of the arms, and the maximum number of secondary teeth on hook-shaped arm spines in distal portion of the arms (Table 1, see also remarks for A. spinulosum)., Published as part of Okanishi, Masanori & Fujita, Toshihiko, 2018, A taxonomic review of the genus Astrodendrum (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) with description of a new species from Japan, pp. 289-310 in Zootaxa 4392 (2) on pages 307-309, DOI: 10.11646/zootaxa.4392.2.4, http://zenodo.org/record/1195409, {"references":["Doderlein, L. (1902) Japanische Euryaliden. Zoologishcer Anzeiger, 25, 320 - 326.","Doderlein, L. (1911) Beitrage zur Naturgeschichte Ostasiens. Uber japanische und andere Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften, II. Suppl. - Bd., 5, 1 - 123.","Bomford, T. L. (1913) A note on certain ophiuroids in the Indian Museum. Records of the Indian Museum, 9, 219 - 225.","Matsumoto, H. (1917) A monograph of Japanese Ophiuroidea, arranged according to a new classification. Journal of College of Science Imperial University of Tokyo, 38, 1 - 408.","Murakami, S. (1944) Report on the ophiurans from off Ogasawara Islands and from off the Yaeyama group, Nippon. Journal of the Department of Agriculture, Kyushu Imperial University, 7, 235 - 257.","Chang, F. Y., Liao, Y. L. & Wu, B. J. (1962) Euryales (Echinodermata: Ophiuroidea: Euryalida) of China. Acta Zoologica Sinica, 14, 53 - 67.","Irimura, S. (1991) Ophiuroidea. In: Echinoderms from continental shelf and slope around Japan. Vol 2. Japan Fisheries Resource Conservation Association, Tokyo, pp. 111 - 153.","Irimura, S. and Kubodera, T. (1998) Ophiuroidea in the East Chinae Sea. Memoires of the National Science Museum, 30, 135 - 143.","Irimura, S. (1982) The Brittle-stars of Sagami Bay. Maruzen Co. Ltd., Tokyo, 95 pp."]}

Astrodendrum capense (Mortensen, 1933) (Figs 8, 9) Astroconus capensis Mortensen, 1933. 285–288, fig. 19a–e;— A. M. Clark & Courtman-Stock, 1976. 132. Astrodendrum capensis— Baker, 1980. 58; Alva & Vadon, 1989. 831, fig. 1c–d. Type materials. ZMUC OPH-80, holotype, collected by Fisheries Survey, northeastern Durban, South Africa, 29˚51.00’S, 31˚28.00’E, 415 m deep, August 1929 (Fig. 1). Diagnosis. External ossicles granular, fully in contact and large conical, separated on aboral disc; external ossicles plate shaped, fully in contact and conical, separated on interradial lateral disc; external ossicles plateshaped, fully in contact on oral surface of disc; bulges of lateral edges of proximal portion of arms absent; 2 or 3 terminal projections on each arm spine in proximal portion of arm; 1 or 2 secondary teeth on each hook-shaped arm spine in distal portion of arm. Description of holotype. Disc. Disc five-lobed with notched interradial edges, 60 mm in disc diameter (Fig. 8A). Radial shields tumid (Figs 10A, C, D). Aboral disc entirely covered by small granular external ossicles, fully in contact, and large conical external ossicles, separated and scattered on radial shields and lateral marginal edge of disc (Fig. 8A, B, F). Granular external ossicles approximately 100–150 µm in length (Fig. 8E, F). The large conical external ossicles approximately 400–1300 µm in length on radial shields and 350–750 µm in length at lateral marginal edge of disc (Fig. 8F). Radial shields completely concealed by external ossicles, bar-like, approximately 12 mm in length, 3 mm in width, and almost reaching disc center (Fig. 8C). Oral surface of disc covered by flat, polygonal plate-shaped external ossicles, fully in contact, approximately 300–450 um in length (Figs 8G, H, 11A). Oral shields, adoral shields, oral plates and ventral arm plates completely concealed by external ossicles (Fig. 8G). Uniformly flat and spiniform teeth on dental plates, approximately 2.5–6 mm length and approximately 10 on each dental plate (Fig. 8H). Smaller acute and spine formed teeth on edge of each oral plate, approximately 1.2–2.0 mm in length and 12–14 in number (Fig. 8H). Interradial surface of lateral disc covered by flat plate-shaped external ossicles, fully in contact, and conical external ossicles, separated and scattered (Fig. 9B). Plate-shaped external ossicles approximately 100 um in length and granular external ossicles approximately 100–150 um in length (Fig. 9B). Two genital slits (4.6 mm long and 0.6 mm wide) in each interradius (Fig. 8B). Minute spinule ossicles along genital slits, 70–80 µm in length (Fig. 8B, E). One inconspicuous large, elliptical madreporite situated on an oral interradius, approximately 5 mm in length and 1.5 mm in height (Fig. 8G). Arms. Arms five, branching at least 8 times but further branches interminate because of entanglement of arms (Fig. 8A, B). First branch occurring outside of disc (Fig. 8B). On the proximal portion of the arm, the width and height almost equal, 6.5 mm with an arched aboral surface and flattened oral surface (Fig. 8B). Arms tapering gradually towards arm tip (Figs 10B; 11C, D, F. F–H). On aboral and lateral surface of the proximal portion of arm, each arm segment covered by plate-shaped external ossicles, fully in contact, approximately 150–200 µm in length (Fig. 9C). Hooklet-bearing plates inconspicuous, approximately 300 µm in length and separated, but not carrying hooklets before third branch (Fig. 9C), in contact and forming transverse rows after fourth branch (Fig. 9D). Throughout the arm, secondary hooklet present on hooklets. In middle portion of arm, aboral and lateral surfaces covered by plate-shaped external ossicles, fully in contact, approximately 120 µm in length (Fig. 9D, G). Oral surface of proximal portion of arms covered by flat, polygonal plate-shaped external ossicles, fully in contact, approximately 280–650 µm in length (Fig. 9E). In middle portion of arm, oral surfaces covered by flat, slightly tumid plate-shaped external ossicles, slightly in contact, approximately 100–180 µm in length (Fig. 9F). Those external ossicles disappearing on distal portion of the arms (Fig. 9H). Throughout arm, lateral and ventral arm plates completely concealed by skin or external ossicles (Fig. 8C–H). Tentacle pores small and almost invisible in external view (Fig. 8G). The first to third tentacle pores with no arm spine; fourth pores occasionally with 2 arm spines, fifth and subsequent pores with 3 (rarely 4) spines (Fig. 9F, G). In distal portion of the arm, the number of arm spines decreasing gradually to 1 toward arm tip (Fig. 9H). Arm spines on proximal portion of the arms ovoid, carrying 2 or 3 terminal projections. Innermost arm spines one-fourth the length of the corresponding arm segment, and outer spines two-thirds the length of inner spines (Fig. 9E). Arm spines on middle portion of arm cylindrical, carrying 2 terminal projections (Fig. 9F). Innermost arm spines half of length of corresponding arm segments, gradually decreasing in length to one-sixth length of corresponding arm segments toward outer spine (Fig. 9F, G). In the distal portion of arms, arm spines transforming into hooks with 2 secondary teeth, approximately two-thirds length of the corresponding arm segments (Fig. 9H). Color. Uniformly white, interradial disc areas slightly darker (Fig. 8A, B). Distribution. REPUBLIC OF SOUTH AFRICA. Off Durban, southeastern Africa (type locality, Mortensen, 1933). NAMIBIA. West off Namib-Naukluft National Park, southwestern Africa (Alva &Vadon, 1989; Olbers, 2016). Depth range 161–478 m (Fig. 1). Remarks. Astrodendrum capense is related to A. elingamita in possessing small granular external ossicles, fully in contact on aboral disc. A. capense and A. elingamita can be distinguished by absence/presence of large conical spines on radial shields and the maximum number of secondary teeth on hook-shaped arm spines (Table 1, see also remarks for A. spinulosum sp. nov.)., Published as part of Okanishi, Masanori & Fujita, Toshihiko, 2018, A taxonomic review of the genus Astrodendrum (Echinodermata, Ophiuroidea, Euryalida, Gorgonocephalidae) with description of a new species from Japan, pp. 289-310 in Zootaxa 4392 (2) on pages 301-302, DOI: 10.11646/zootaxa.4392.2.4, http://zenodo.org/record/1195409, {"references":["Mortensen, T. (1933) Echinoderms of South Africa (Asteroidea and Ophiuroidea) Papers from Dr. Th. Mortensen's Pacific Expedition 1914 - 16. Videnskabelige Meddelelser fra Dansk naturhistorisk Forening, 93 (65), 215 - 400.","Clark, A. M. & Courtman-Stock, J. (1976) The echinoderms of southern Africa. Publication No. 766. British Museum (Natural History), London, 277 pp.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","Alva, V. & Vadon, C. (1989) Ophiuroids from the western coast of Africa (Namibia and Guinea Bissau). Scientia Marina, 53 (4), 827 - 845."]}

Astrocladus goodingi sp. nov. (Figs. 7A–C, 8–11) Astrocladus tonganus.— Cherbonnier & Guille, 1978: 14, Pl. II figs. 3–4. Non Astrocladus tonganus Döderlein, 1911: 77, 107, pl. 9 fig.8. Material Examined. Holotype USNM 1072479, Anton Bruun Cruise 9, Indian Ocean, Comoro Islands, Mayotte Island, Bandeli Reef, 12° 54’S, 45° 16.5’E, inner side of reef, depth approximately 1 m, 23–26 November 1964. Collected by R.U. Gooding (RU-297), 1 specimen, disc diameter 15 mm (Figs. 7–10). Other material examined. Three specimens from localities in the northwest and south of Madagascar, identified by Cherbonnier & Guille 1978 as Astrocladus tonganus Döderlein (sent to ANB by the late Dr A. Guille, specimens now in Muséum National d’Histoire Naturelle, Paris). The three specimens were referenced by Baker (1980, p. 64). Their current catalogue numbers were unavailable. Etymology. Named for the collector, the late Dr R.U. “Judge” Gooding of Barbados; our friend and colleague. Diagnosis. Disc and radial shields with tubercles bearing 2–8 glassy spines; five arm spines bearing 1–5 glassy spinules, present from third arm segment; girdle bands present from disc margin; arm areas between girdles and orally with large polygonal plates, separated by narrow rows of small single plates. Genital slits bordered abradially by a row of tall spines. Description of the holotype. External morphology. Aboral disc depressed at center, aborally with scattered small Ossicle morphology. Hooklet-bearing plates possessing approximately 16 tubercle-shaped articulations for hooklets in the basal portion of the arm (Fig. 10A), approximately 6 articulations in the distal portion (Fig. 10H). The articulations forming two parallel rows (Fig. 10A, H). Each hooklet bears one inner tooth (Fig. 10B–C). Lateral arm plates concave on distal and basal sides, the concavity deeper on distal side (Fig. 10D–E). No perforations visible on lateral arm plates but simple nerve openings on oral-external side (Fig. 10E–F) and on distal portion of the arms; articulations for hooklets only visible on oral surfaces (Fig. 10H). Arm spines in the basal portion of the arm ovoid and having one secondary point, approximately one-third length of the height of the spine (Fig. 10I). All vertebrae with hourglass-shaped streptospondylous articulations (Fig. 11D–E, H–I). Depressions for tube feet openings in the distal part of oral-lateral side of vertebrae (Fig. 11A, G). A pair of radial water canals opening on the lateral side of vertebrae, near depression of the tube feet (Fig. 11A, G) and radial nerve canals opening inside oral furrows (Fig. 11A). Remarks. The genus Astrocladus contains 10 nominal species, of which five are now know from the Indian Ocean or nearby: A. hirtus Mortensen, A. euryale (Retzius), A. exiguus (Lamarck), A ludwigi (Döderlein), and A africanus Mortensen. Adding a further species to this fauna may seem an unnecessary complication, especially given the intra-species variations and similarity in morphology of A. euryale and Astrodendrum capensis (Mortensen, 1933b) as noted by A. M. Clark (1974) in her account of echinoderms from Southern Africa. We have, however, examined the descriptions of all the Astrocladus species, and cannot reconcile the Comoro and Madagascar specimens with any known taxon. Cherbonnier & Guille (1978) referred five specimens of an Astrocladus collected in northwestern and southern Madagascar, to A. tonganus Döderlein, 1911 a species previously known only from the Pacific Ocean near the Tonga Islands. Baker (1980, p. 64) compared some of their material with A. tonganus from the Pacific type locality, and found that it represented a “species allied to A. hirtus ”. The Cherbonnier & Guille (1978) material is referred here to A. goodingi sp. nov. A. tonganus has a disc covering of conical tubercles bearing 1–2 glassy spines, but there the external similarity with A. goodingi ends: the arms of A. tonganus are covered above with flat plates and pointed tubercles and below with closely set small plates, the girdle belts are continuous only after the 7th arm bifurcation, and the genital slits are not bordered by tall spines. A. hirtus from “Natal or Mozambique ”, is perhaps closer to A. goodingi sp. nov., but differs mainly in that it has fewer glassy spines on the disc tubercles, radial shields bearing slender papillae, and complete belts of girdle hooklets from the 6th arm bifurcation (Mortensen, 1933b; A. M. Clark & Courtman-Stock, 1976). The distinguishing features of A goodingi sp. nov. are: Disc and radial shields bearing conical tubercles with 2–8 terminal glassy spines (Fig. 9B–C); Five arm spines bearing 1–5 terminal glassy spinules (Fig. 10I), present from third arm segment; Genital slits narrow and short, bordered abradially by a row of tall spines (Fig. 9F); Girdle bands present from disc margin, and complete between first and second arm branch (Fig. 9A); Arm surface, orally and between girdles covered with large polygonal plates, separated by narrow rows of small single plates (Fig. 9A). Distribution. Western Indian Ocean including Mayotte Island (type locality) and the Mozambique Channel., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on pages 11-14, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Cherbonnier, G. & Guille, A. (1978) Faune de Madagascar. 48. Echinodermes: Ophiurides. Memoires ORSTOM, Paris, 272 pp.","Doderlein, L. (1911) Beitrage zur Naturgeschichte Ostasiens. Uber Japanische und andere Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften II, Supplement Band 5, 1 - 123.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","Mortensen, T. (1933 b) Echinoderms of South Africa (Asteroidea and Ophiuroidea). Videnskabelige Meddelelser fra Dansk naturhistorisk Forening I Kjobenhaven, 93, 215 - 400.","Clark, A. M. (1974) Notes on some Echinoderms from Southern Africa. Bulletin of the British Museum of Natural History (Zoology), 26 (6), 423 - 487. https: // doi. org / 10.5962 / bhl. part. 210","Clark, A. M. & Courtman-Stock, J. (1976) The Echinoderms of Southern Africa. British Museum of Natural History, London, 277 pp."]}

Family Gorgonocephalidae Ljungman, 1867 Diagnosis. Arms simple, or branching, coiled. Disc five lobed or circular, covered with skin and/or various shaped external ossicles. Hooklets borne on at least middle to distal portion of aboral arms. Teeth spiniform. Radial shields narrow, multi-layered. Ventral arm plates limited to basal few arm segments. Up to more than ten arm spines. Genital slits usually small, approximately one half of the height of the disc., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on page 9, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Ljungman, A. (1867) Ophiuroidea viventia huc usque cognita enumerat. Ofversigt af Kungliga Vetenskapsakademiens forhandlingar, Stockholm, 1866 (9), 303 - 336."]}

Order Euryalida Lamarck, 1816 Diagnosis. See Okanishi & Fujita (2013) for the composition of this order., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on page 2, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Lamarck, J. B. P. (1816) Stellerides. In: Histoire naturelle des animaux sans vertebres. Edition 1.2. Verdiere, Paris, pp. 522 - 568."]}

Astrocyclus somaliensis sp. nov. (Figs. 17A–C, 18–21) Material Examined. Holotype: USNM 1411388 Anton Bruun station 9–463, 11˚ 24’ N, 51˚ 35’ E, 75–175 m, 18 December 1964, off the north-eastern coast of Somalia, 1 specimen, disc diameter 27 mm (Fig. 16). Paratypes: USNM 1422067, same locality data as holotype, 3 specimens, disc diameter 24, 16 and 10 mm. Etymology. The specific name refers to the collection locality. Diagnosis. Astrocyclus with aboral surface of disc depressed centrally, radial shields converging at center. Radial shields partly covered with more or less continuous transverse thin white lines made up of closely packed granules (6–8/mm), which loop over the shields and partly extend into the inter-shield and interradial areas. Description of the holotype. External morphology. The disc five-lobed, 27 mm in disc diameter, with arms at least 115 mm long (Fig. 17A–B). The disc markedly depressed centrally (Fig. 18A); narrow, raised, radial shields converging there (Fig. 18A–B). The entire aboral surface, including the area between each of the radial shields, covered with evenly spaced low granules (Fig. 18A–B). The radial shields partly covered with more or less continuous transverse white lines made up of microscopic, closely packed granules (6–8/mm), which loop over the radial shields, with some partly extending into the inter-shield and inter-radial areas of the disc. The arm segments are conspicuously ringed laterally and aborally by narrow bands of microscopic granules, mostly in two rows, which stand out from the surface (Fig. 19B–D). There are two, then three, small arm spines with hyaline tips per segment (Fig. 18D–F). The distalmost arm segments have girdle bands, with strongly curved hyaline hooklets (Fig. 19D). The oral surface of the arms and disc are covered with evenly spaced granules, and there is one madreporite in each of the five interradial disc areas, jaws entirely covered by spiniform teeth and oral papillae (Fig. 18C). Ossicle morphology. All vertebrae with hourglass-shaped streptospondylous articulations (Fig. 20C–D, G–H). Surfaces of lateral and aboral furrows smooth, without ornamentations (Fig. 20A–B, E–F). Depressions for tube feet openings in the distal part of oral-lateral side of vertebrae (Fig. 20A, F). A pair of radial water and nerve canals opening on the oral groove of vertebrae on basal portion of the arm (Fig. 20A) but radial nerve canals invisible on distal portion of the arm (Fig. 20F). Lateral arm plates long, bar-like, with straight basal edge and concave distal edge (Fig. 20I –J). On basal portion of arm, perforation invisible on aboral side and pairs of simple nerve openings on oral-external side (Figs. 20J, 21A). Hooklet-bearing plates possessing tubercle-shaped articulations for hooklets, approximately 7 on distal portion of the arm (Fig. 21B). The articulations forming two parallel rows (Fig. 21B). Each hooklet without inner teeth (Fig. 21G–H). Arm spines in the basal portion of the arm ovoid, with one or two secondary points (Fig. 21D–E). In the distal portion, the arm spines transformed into hooks with one inner teeth (Fig. 21F). The hook-shaped arm spines distinguished from hooklets on aboral and lateral surface of the arm by lacking reticular structure (Fig. 21F–H). Variation. In the smallest specimen (USNM 1422067, dd. 10 mm), the entire area between the shields is covered with transverse lines. This feature differs from that in the Brazilian samples described and illustrated by Gondim et al (2014), where between each radial shield there are 6–7 discrete groups of granules running in line with the shields (Fig. 17D). In the two larger specimens (USNM 1411388, dd. 27 mm; USNM 142 2067, dd. 24 mm), a few of these lines of granules extend between the shields. Remarks. As all four examined specimens from the Indian Ocean have similar disc and radial shield coverings which differ markedly from the western Atlantic specimens, we consider that they represent a separate taxon, which we here establish as a new species. The arms bifurcate at least 15 times, the first branch within the diameter of the disc, and the second at the distal end of the radial shields (Fig. 17A–B). Astrocyclus caecilia has been recorded from the Caribbean Sea, Gulf of Mexico (type locality), and from northeastern Brazil by Gondim et al. (2014), who have illustrated the species extensively. The vast geographical separation of the type species and the Somalian form, plus the obvious morphological difference in the covering of the radial shields and their interradial aboral areas, indicate that a new species, Astrocyclus somaliensis sp. nov. should be erected for this Somalian form.

Astroglymma sculptum (Döderlein 1896) (Fig. 22) Astrophyton sculptum Döderlein, 1896: 299, pl.18 fig. 29. Astroglymma sculptum.— Döderlein, 1927: 47, pl. 1 fig. 3,4; pl. 5 fig. 13. Baker, 1980: 66, figs. 19, 28, 31; Liao & A. M. Clark, 1995: 170, fig. 74; Rowe & Gates, 1995: 365. Astroglymma robillardi.— Mortensen, 1933a:34, pl. 3 figs. 1,2; pl. 4 fig. 1. Material Examined. USNM 1072476, Anton Bruun Cruise 8 Station 394B, off Durban, 29° 27’ S, 31° 31’ E, 68– 70 m, 29 September, 1964, 3 specimens plus arm fragments of a 4th. USNM 1072575, Anton Bruun Cruise 8 Station 403E, off Mozambique, 19° 09’ S, 36° 55’ E, 88 m, 2 specimens, 9 October 1964. USNM 1233996, Anton Bruun Cruise 8 Station 394A, Off Durban, South Africa, 29° 26’ S, 31° 32’ E, 68 m, 25 September 1964, 1 specimen. Remarks. Two specimens from Station 394B are very large (dd. 76 and dd. 81 mm) and are typical of the species (Fig. 22A–B). A medium-sized specimen (dd. 30 mm) is uniformly covered with fine pustules and occasional larger ones (Fig. 22C–E). The arms are bifurcated 16–17 times and carry girdle bands after the first branch. Otherwise the description matches that in Baker, (1980 p. 66) of material from the eastern Indian Ocean. Distribution. Originally described from USFC Albatross material from the Philippines, this shallow water basket star is widely distributed in the Indo-Malaysian region, and in the east China Sea in 73–300m depth (Baker, 1980), and its occurrence off Durban and further north off Mozambique, is not unexpected., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on pages 22-23, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Doderlein, L. (1896) Bericht uber die von Herrn Prof. Semon bei Amboina und Thursday Islands gesammelten Ophiuroidea. In: Semon, R. W. Zoologische Forschungsreisen in Australien und dem Malayischen Archipel. Jenaische Zeitschrift fur Medizin und Naturwissenschaft, 8, 279 - 300.","Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematischnaturwissenschaftliche Abteilung, 31 (6), 1 - 105.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763","Liao, Y. & Clark, A. M. (1995) The echinoderms of southern China. Science Press, Beijing, 614 pp.","Rowe, F. W. E. & Gates, J. (1995) Echinodermata. In Wells, A. (Ed.), Zoological Catalogue of Australia. Vol. 33. CSIRO Australia, Melbourne, pp. 1 - 510.","Mortensen, T. (1933 a) Studies of Indo-Pacific Euryalids. Videnskabelige Meddelelser fra Dansk naturhistorisk Forening I Kjobenhaven, 96, 1 - 75."]}

Astroboa nigrofurcata D��derlein, 1927 (Figs. 6A���E, 7D) Astroboa nigrofurcata D��derlein, 1927: 45, pl. 4 figs. 1���4; Baker, 1980: 60, figs. 23, 28, 30. Material Examined. USNM 1072537, Anton Bruun Cruise 1 Station 18A, southern Andaman Sea, 7��34���N, 98�� 00���E, 77 m, 21 March 1963, 2 specimens (Fig. 6A���E); USNM 1234012, Anton Bruun Cruise 9 Station 465, off NE Somalia, 11�� 37���N, 51�� 27���E, 67���72 m, 18 December 1964, 2 specimens. Remarks. The specimens range between 17 and 40 mm (Fig. 6A���B) disc diameter. The smallest specimen has a disc cover of dense low granules, 8 in 1 mm on the radial shields (Fig. 6C). One unusual feature of this specimen, possibly related to its small size, is the presence of 2���4 transverse rows of taller granules bridging the pairs of radial shields. In the largest specimen, the arms bifurcate at least 25 times, and are covered with smooth polygonal plates, with prominent girdle bands continuing over the arm���a characteristic of this species (Figs. 6D���E, 7D). The colour pattern of this species is distinctive���disc pale green, with contrasting irregular brown or pink freckles; arms with a continuous series of dark freckles, one per segment. This record, in the southern Andaman Sea, is an extension of the known range from the Western Australian coast, Indonesia and the Philippines (Baker 1980)., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on page 9, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematischnaturwissenschaftliche Abteilung, 31 (6), 1 - 105.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763"]}

Asteronyx luzonicus Döderlein, 1927 (Figs. 4F–G, 5A–C) Asteronyx luzonicus Döderlein, 1927: 64, pl. 7 figs. 4–6d. Material Examined. USNM 1072474, Anton Bruun Cruise 1 Station 17, southern Andaman Sea, 7° 38’ N 97° 09’ E, 280– 275 m, 21 March 1963, 1 specimen; Anton Bruun Cruise 7 Station 369F, off southern Mozambique, 24° 07’S, 36° 11’–15’E, 1600–1628 m, 17 August 1964, 1 specimen. Remarks. The disc diameters of the two specimens are 15 mm (Fig. 4F–G) and 6 mm respectively. The larger specimen has narrow arms approximately 140 mm long (Fig. 4F–G). The larger specimen has a naked skin-covered disc with dark spots aborally and orally (Fig. 5A–B), and with some light calcification between one pair of radial shields (Fig. 5A). The genital slit is narrow, situated between arm segments 1 and 3, and is not in a pouch (Fig. 5B), as in the type species, A. loveni. At arm segment 22, the lowermost arm spine is elongate, with a terminal club (Fig. 5C). This elongate arm spine is not present on the smaller specimen, and may therefore be ontogenetic as is the number of arm spines. A similar enlargement of mid-arm spines has been noted in A. loveni (Baker 1980). The dark spots on their disc is a main diagnostic character of A. luzonicus (Döderlein, 1927). This species has remarkable bathymetric distribution, between 109 and 2963 m. A. luzonicus was originally described from the Philippines; its occurrence in the southern Andaman Sea and the Mozambique Channel represents a considerable extension of its geographic range, but one that might be expected given its bathymetric range., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on pages 7-8, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Doderlein, L. (1927) Indopacifische Euryalae. Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematischnaturwissenschaftliche Abteilung, 31 (6), 1 - 105.","Baker, A. N. (1980) Euryalinid Ophiuroidea (Echinodermata) from Australia, New Zealand, and the south-west Pacific Ocean. New Zealand Journal of Zoology, 7, 11 - 83. https: // doi. org / 10.1080 / 03014223.1980.10423763"]}

Family Asteronychidae Verrill, 1899 Diagnosis. Arms simple, coiled. Disc five lobed or circular, covered with skin and/or plate-shaped external ossicles. Teeth spiniform, covering whole side of jaw. Radial shields narrow, multi-layered. Ventral arm plates limited to a few basal arm segments. Up to more than ten arm spines. Genital slits usually small, half the length of the height of the disc., Published as part of Baker, Alan N., Okanishi, Masanori & Pawson, David L., 2018, Euryalid brittle stars from the International Indian Ocean Expedition 1963 - 64 (Echinodermata: Ophiuroidea: Euryalida), pp. 1-27 in Zootaxa 4392 (1) on page 7, DOI: 10.11646/zootaxa.4392.1.1, http://zenodo.org/record/1194434, {"references":["Verrill A. E. (1899) North American Ophiuroidea. I. Revision of certain families and genera of West Indian ophiurans. Transactions of the Connecticut Academy of Sciences, 10 (7), 301 - 371."]}