Search

Canthocamptus waldemarschneideri sp. nov. urn:lsid:zoobank.org:act: 3977FD97-8727-4DEA-BFEF-96DCA66A6BE5 Figs 1–9; Table 2 Canthocamptus sp. 1 – Novikov et al. 2021: 268. Etymology The species is named after Mr Waldemar Schneider, who helped us during the eXpedition. Material examined Holotype RUSSIA • ♀ (on 2 slides); Lena River Delta, small channel near Mount America-Haia; 72.467560° N, 126.285025° E; depth 1–1.5 m; 21 Aug. 2019; A. Novikov leg.; KFU BP 544/1-a, BP 544/1-b. Allotype RUSSIA • ♂ (on 2 slides); same collection data as for holotype; KFU BP 544/2-a, BP 544/2-b. Paratypes RUSSIA • 1 ♂, 1 ♀ (undissected; microtube); same collection data as for holotype; KFU BP 544/4 • 1 ♀; Lena River Delta, Krugloe Lake; 72.468859° N, 126.265658° E; depth 1–1.5 m; 21 Aug. 2019; A. Novikov leg.; KFU. Other material RUSSIA • 1 ♂; Lena River Delta, Samoylov Island, Yuzshnoe Lake; 72.369653° N, 126.509606° E; depth 1–1.5 m; 4 Aug. 2019; A. Novikov leg.; KFU • 2 ♂♂, 1 ♀; Lena River Delta, Samoylov Island, Ruiba Lake; 72.373173° N, 126.486302° E; depth 1–1.5 m; 4 Aug. 2019; A. Novikov leg.; KFU. Description Female (based on holotype) BODY. Subcylindrical (as in Fig. 1A). Total body length from anterior margin of rostrum to posterior margin of caudal rami: 904 µm. CephalothoraX (Fig. 2A–B) with blue naupliar eye, wider than remaining somites, largest width 204 µm. Rostrum small, fused with cephalothoraX, with one pair of sensilla and one pore. Posterior margin of cephalothorax and all pedigerous somites slightly serrated. ABDOMEN (Fig. 3). Consisting of genital double-somite, two free abdominal somites and anal somite with caudal rami. All somites eXcept anal somite serrated on posterior margin, on surface with rows of small spinules. Genital double-somite wider than long; with seven pairs of sensilla, two pairs of lateral pores, paired ventral group of three pores, one unpaired ventral pore and two dorsal unpaired pores; on posterior margin with dorso-lateral row of spinules and small ventral row of spinules. P6 (Fig. 3B) fused with somite with one pinnate and one naked seta. Genital field (Fig. 3B) long, laterally with sieves; copulatory pore in middle of somite, copulatory duct strongly chitinised with two additional tubes, eXtending proXimally to pair of labyrinthic rounded ducts. First free abdominal somite with three pairs of sensilla, one dorsal pore, one pair of lateral pores and five ventral pores; on posterior margin with dorso-lateral row of large spinules and ventral row of small spinules. Second free abdominal somite with one dorsal pore, pair of lateral pores and one ventral pore, on posterior margin with circumsomitic row of spinules. Anal somite with one pair of sensilla, three pairs of pores on ventral, dorsal and lateral sides, and ventral rows of spinules. Anal operculum semilunar, with four long spinules. CAUDAL RAMI (Fig. 3). Length/width ratio 2, with two ventral pores; with rows of spinules on distal margin and rows of spinules at base of setae II and III. Seta I small, located near seta II. Apical seta IV (Fig. 1B) short, spinulose, with ʻhelle Stelleʼ (sensu Lang 1948). Apical seta V long, spinulose, with bulb at base. Length of apical setae IV and V 92 µm and 556 µm respectively. Seta VII triarticulated (Fig. 1A). ANTENNULE (Fig. 4A). 8-segmented. Segment 1square, with one pinnate seta and two rows of spinules.Other segments with bare setae. Segment 4 with seta and aesthetasc fused basally. Distal segment with acrothek consisting of aesthetasc and two setae fused basally. Armature formula: 1-[1],2-[9],3-[5],4-[1+(1+ae)],5- [1],6-[3],7-[2],8-[5+acr]. ANTENNA (Fig. 4B). With allobasis. Coxa with three spinular rows. Allobasis with two pinnate setae and one spinular row. Free endopodal segment with two lateral rows of big spinules, with two spinulose spines and slender seta; distally with two rows of spinules; apically with three geniculate setae, two long spines and one small accessory seta; outermost geniculate seta fused basally with small seta. Exopod 2-segmented; first segment with one unipinnate seta; second segment with three bipinnate setae. LABRUM (FIG. 1C). Typical for Canthocamptidae. On outer side with row of thin setulles and a pore. On inner side with lateral rows of big spinules and rows of spinules fused into comb; with distal spinules and proximal groups of very thin setulles. MANDIBLE (FIG. 1D). Coxa with spinules proximally. Gnathobase with few multicuspidate teeth and spinulose seta; pars incisiva with one process; lacinia mobilis with two blunt teeth. Pars molaris sharply- edged. Palp consisting of free basis and 1-segmented endopod. Basis with row of spinules; endopod with two spinular rows, one pinnate proXimal seta and four naked distal setae. MAXILLULE (Fig. 4C–D). Praecoxa with two rows of slender spinules on outer edge and one row of spinules on posterior side. Praecoxal arthrite medially with row of spinules; with seven strong distal spines, distal seta with long spinules and two proXimal setae. CoXa with row of slender spinules, coXal endite with one pinnate and spinulose setae. Basis with two groups of spinules, two subdistal setae and three distal setae. Endopod and eXopod incorporated into basis, each represented by protuberance with two pinnate setae. MAXILLA (Fig. 5A). Basis with several rows of spinules on outer and inner edge as figured, with two endites. ProXimal endite with one strong bipinnate seta, two pinnate setae and spinular row, distal endite with three pinnate setae. ProXimal endopodal segment with two setae, small process near one of setae and massive distal claw. Distal endopodal segment with three naked setae. MAXILLIPED (Fig. 2C). Subchelate. SyncoXa elongated with several rows of spinules as figured, distally with one unipinnate seta. Basis with two rows of large spinules on anterior and posterior sides and three outer rows of small spinules. Endopod on posterior side with one seta. Endopodal claw elongated, with five small spinules. P1 (Fig. 5B). With 3-segmented rami. PraecoXa with row of spinules. CoXa rectangular, with eight spinular rows. IntercoXal sclerite wide, with one pair of spinular rows. Basis with proXimal pore, medial row of spinules, rows of spinules at base of endopod and eXopod, row of spinules at base of inner seta and two inner rows of spinules; with strong inner and outer spines. All endopodal and exopodal segments with outer spinules. First eXopodal segment with one outer spine; second segment with inner spinular row, inner seta and outer spine; third exopodal segment with two outer spines and two slender apical geniculate setae. Endopod longer than eXopod. First endopodal segment reaching middle of third eXopodal segment, with inner seta and inner spinular row; second endopodal segments with one inner seta, third segment with outer spine, long apical geniculate seta and small inner seta. P2 (Fig. 6A). Praecoxa with row of spinules. Coxa with one lateral row of spinules and six rows of spinules on anterior side. IntercoXal sclerite with two paired spinular rows. Basis with proXimal pore, medial row of spinules, two rows of slender spinules on inner edge and rows of spinules at base of endopod and exopod; with outer spine.All endopodal and exopodal segments with outer spinules. Exopod 3-segmented; first eXopodal segment with outer spine, inner row of slender spinules and apically with frill; second segment with outer spine, inner seta, inner spinules and apical frill; third segment with three outer spines, two apical setae and one inner seta. Endopod 3-segmented; first and second segments with inner setae and inner spinular rows; third segment with inner spinular row, small outer spine, two apical setae and one inner seta. P3 (Fig. 6B). Similar to P2. PraecoXa, coXa, basis, first and second eXopodal segments and first and second endopodal segments as in P2. Intercoxal sclerite with only one paired spinular row. Third exopodal segment with three outer spines, two apical setae and two inner setae. Third eXopodal segment with outer spine, two long apical setae and two inner setae with pectinate tip. P4 (Fig. 6C). Similar to P2. PraecoXa, coXa and basis as in P2. IntercoXal sclerite with only one paired spinular row. EXopod as in P2, but third eXopodal segment with two inner setae with strong spinules. Endopod small; first segment with inner seta; second segment with outer spine, two apical setae and two inner pectinate setae; outer apical seta short, about as long as outer spine. P5 (Fig. 5C). With separate right and left baseoendopods. Baseoendopod reaching about proximal third of eXopodal segment; with three pores, spinular row at base of outer seta; outer seta of basis naked. Endopodal lobe with five long bipinnate setae and one minute seta between fourth and siXth normal setae. EXopod with three equal outer setae, one long apical seta and minute inner seta. Male Total body length from tip of rostrum to posterior margin of caudal rami: 765 µm. Sexual dimorphism eXpressed in the antennule, P2–P6, genital segmentation and ornamentation. CephalothoraX and thoracic somites as in female. P6 (Fig. 7B) two asymmetric flaps fused to somite, with two slender setae and pinnate inner spine. Anal somite and caudal rami as in female, but seta V without bulb at base. Anal operculum with five spinules. ANTENNULE (Fig. 8A–B). 10-segmented, haplocer with geniculation between segments 7 and 8. Segment 5 with large aestetasc fused at base with long seta. Segment 7 with articular plate, with one filiform seta, one pinnate seta and with two modified laminar setae. Segment 8 with 3 similar modified laminar setae. Segment 10 with acrothek consisting of slender aesthetasc and two setae. Armature formula: 1-[1],2- [9],3-[8],4-[2],5-[7+(1+ae)],6-[2],7-[2+2 modified],8-[3 modified],9-[1],10-[7+acr]. P2 (Figs 9A, 10A–B). PraecoXa, coXa, intercoXal sclerite and basis as in female. EXopod as in female, but segments broader and shorter. Endopod 2-segmented. First segment as in female. Second segment long, with well-defined border between original segments evidenced by proXimal inner seta and outer cuticular process; with two apical setae and two inner setae. P3 (Figs 9B, 10C–D). PraecoXa, coXa, intercoXal sclerite and basis as in female. EXopod as in female, but segments broader and shorter. Endopod 3-segmented. First endopodal segment with slender seta and cuticular process on posterior side. Second endopodal segment with one small posterior seta and long apophysis with tip. Third segment with two small inner setae and one apical pinnate seta and one apical naked seta. P4 (Fig. 9C). PraecoXa, coXa, intercoXal sclerite and basis as in female. EXopod as in female, but segments broader and shorter, and outer spines of third eXopodal segment curved. Endopod 2-segmented; first segment with inner seta; second segment with outer spinules, outer seta modified into finger-like process, two long apical setae and two pectinate inner setae. P5 (Fig. 8C). Asymmetric; right and left P5 fused medially. Baseoendopod with four pairs of pores, outer spinular row and long outer naked seta; endopodal lobe with strong apical spine and small inner seta; left lobe with spinule near distal margin. EXopod with three equal in length outer setae, long apical seta, one minute inner seta and one long inner pectinate seta. Difference between left and right eXopods is that left one has much longer inner seta and shorter proximal outer spine. Ecology The species was found in four water-bodies of the Lena River Delta. The type locality at the collection site is a small channel without macrophytes with a silty bottom. The other three reservoirs are typical old thermokarst lakes with a large number of macrophytes and a silty bottom. At the type locality, the species was found with the following Copepoda species: Attheyella nordenskioldii (Lilljeborg, 1902), Bryocamptus nivalis (Willey, 1925), Moraria duthiei (Scott T. & Scott A., 1896), Cyclops kikuchi Smirnov, 1932, Diacyclops bicuspidatus (Claus, 1857), Eucyclops serrulatus (Fischer, 1851), Macrocyclops albidus (Jurine, 1820), Megacyclops gigas (Claus, 1857), Megacyclops viridis (Jurine, 1820), Metacyclops planus (Gurney, 1909), Paracyclops fimbriatus (Fischer, 1853) and Eurytemora gracilicauda Akatova, 1949. Remarks C. waldemarschneideri sp. nov. is closely related to the North American species with four setae on P2 endopod. This is an apparent synapomorphy of this group of species, which also includes C. assimilis Kiefer, 1931, C. robertcockeri M.S. Wilson, 1958 and C. vagus Coker & Morgan, 1940. The new species is closely related to C. assimilis based on similar caudal rami and the shape and length of the setae of P5. The differences between these two species are as follows: 1) the new species has a closed row of spinules on the posterior edge of the third abdominal somite, whereas C. assimilis has a gap on the dorsal side; 2) the caudal seta V of C. waldemarschneideri sp. nov. has a clearly visible thickening at the base, directed upwards; 3) the setal lengths of the male P5 vary more markedly in C. waldemarschneideri sp. nov., especially in the basoendopod, where inner seta/outer seta length = 4.8, whereas in C. assimilis inner seta/outer seta length = 3.1 (Kiefer 1931). Cladistic analysis The result of the cladistic analysis is the puzzled tree shown in Fig. 11A. The length of the tree is 216, and the consistency indeX (CI) and retention indeX (RI) are 0.468 and 0.703, respectively. The most interesting feature was the division of the genus into two groups, one of which (C. mirabilis species group) is closely related to the genera Attheyella and Bryocamptus Chappuis, 1929. Such a division was previously assumed, and this group of species was considered intermediate between the genera Canthocamptus and Attheyella (Ito & Takashio 1980). The most significant characteristic connecting the C. mirabilis species group and the genus Attheyella is the form of the male P2 endopod, with the third segment without an outer seta and with a notch on the distal outer margin (ʻAttheyella-likeʼ endopod, Fig. 11B, character 36). Other synapomorphies of this group include dumbbell-shaped dorsal window (character 4), basis of mandible without setae (character 15), long first endopodal segment of P1 (character 30) and anal operculum with smooth margin (character 69). Based on this and some other differences (Table 7), we propose a new genus, Kikuchicamptus gen. nov., for this monophyletic group. One species, C. gibba, is most closely related to A. nordenskioldii. According to the characteristics described and depicted by Okuneva (1983), this species is completely identical to the studied individuals of the species A. nordenskioldii from the Lena River Delta; therefore, it should be its junior synonym. The Canthocamptus clade is supported by two reliable characters in the structure of the male P2 and P4 endopods: the endopod P2 with fused second and third segment, the third ancestral segment without outer seta, and with a posterio-lateral cuticular process on the border between the second and the third segment (ʻCanthocamptus-likeʼ endopod, character 37); the P4 endopod with modified ʻfinger-likeʼ outer spine (character 50). The division within Canthocamptus s. str. is rather controversial. The entire genus is divided into three large but poorly supported clades. One of the clades includes C. staphilinus and all Baikal species. They were brought together by the similarity in the structure of the male P3 endopod, with a powerful second segment (character 44) and different degrees of reduction in the apical setae (character 43). If this hypothesis is correct, then the simple spine on the male P4 endopod (character 50) of the Baikal species is an apomorphy, not a plesiomorphy. In addition, the placement of the Baikal species C. verestschagini (Borutzky, 1931) and C. longifurcatus Borutzky, 1947 into a separate subgenus, C. (Baikalocamptus) Borutzky, 1931, is also incorrect in this case, since the subgenus Canthocamptus (Canthocamptus), in which Borutzky (1952) proposed to include all other species of the genus, becomes non-monophyletic. Moreover, our own material from Baikal shows that the spine on the male P4 endopod is modified in all the studied males of Canthocamptus sp. However, further research is needed here. Another interesting clade is the C. glacialis species group, which includes C. glacialis, C. sinuus Coker, 1934, C. staphylinoides Pearse, 1905, C. assimilis, C. robertcokeri M.S. Wilson, 1958, C. vagus and C. waldemarschneideri sp. nov. Most species of this group live in North America. The relationship of C. glacialis to the American species was pointed out by M.S. Wilson (1956), though without naming specific common characters. Representatives of the group as a whole are characterized by the primitive structure of the male P2, P3 and P4 endopods (all endopods are slender, with unmodified, normally developed setae). They also lack the characteristic unguiform processes on the anal somite. However, the synapomorphies that combine these species are not sufficiently reliable. These are the loss of outer spinules on the P5 eXopod (character 56) and a large difference between the length of the spines on the P5 baseoendopod of males (character 60). Thus, the monophyly of the clade remains in question. Based on the results of the cladistic analysis, we carry out the following taXonomic changes., Published as part of Novikov, Aleksandr & Sharafutdinova, Dayana, 2022, Revision of the genus Canthocamptus (Copepoda: Harpacticoida) with a description of a new species from the Lena River Delta (North-eastern Siberia), pp. 33-63 in European Journal of Taxonomy 826 (1) on pages 37-52, DOI: 10.5852/ejt.2022.826.1833, http://zenodo.org/record/6761616, {"references":["Lang K. 1948. Monographie der Harpacticiden. Otto Koeltz Science Publishers, Konigstein, Germany.","Lilljeborg W. 1902. Tres species novae generis Canthocampti e Novaja Semlja et Sibiria Boreali, sive Trenne nya Arter af Skaktet Canthocamptus fran Novaja Semlja och Norra Sibirien. Bihang till Kongliga Svenska Vetenskaps-akademiens Handlingar 28 (4): 9.","Kiefer F. 1931. Kurze Diagnosen neuer Susswasser-Copepoden. Zoologischer Anzeiger 94 (5 / 8): 219 - 224.","Wilson M. S. 1958. North American harpacticoid copepods 4. Diagnosis of new species of freshwater Canthocamptidae and Cletodidae (genus Huntemannia). Proceedings of the Biological Society of Washington 71 (1): 43 - 48.","Coker R. E. & Morgan J. 1940. A new harpacticoid copepod from North Carolina. Journal of the Washington Academy of Sciences 30 (9): 395 - 398.","Ito T. & Takashio T. 1980. Canthocamptus mirabilis Sterba (Copepoda, Harpacticoida) from Hokkaido, northern Japan. Annotationes Zoologicae Japonenses 53: 210 - 219.","Okuneva G. L. 1983. New species of Copepoda (Harpacticoida) in the Baikal Lake fauna. Zoologichesky Zhurnal 62 (9): 1343 - 1352.","Borutzky E. V. 1931. Materialen zur Harpacticidenfauna des Baikalsees II. Zoologischer Anzeiger 93: 263 - 273.","Borutzky E. V. 1947. Materials on the fauna of Copepoda, Harpacticoida of Lake Baikal. Genus Canthocamptus Westwood. Doklady Akademii Nauk SSSR 58 (8): 1825 - 1828.","Borutzky E. V. 1952. Crustacea: Freshwater Harpacticoida. Fauna SSSR 3 (4). Izdaniya Akademia Nauk SSSR, Moscow-Leningrad.","Westwood J. O. 1836. Canthocamptus. In: Partington C. F. (ed.) The British Cyclopaedia of Natural History 2: 227. Orr & Smith, London.","Coker R. E. 1934. Contribution to knowledge of North American freshwater harpacticoid copepod Crustacea. Journal of the Elisha Mitchell Scientific Society 50 (1 / 2): 75 - 141.","Wilson M. S. 1956. North American harpacticoid copepods: 1. Comments on the known fresh-water species of the Canthocamptidae. 2. Canthocamptus oregonensis, n. sp. from Oregon and California. Transactions of the American Microscopical Societ y 75 (3): 290 - 307. https: // doi. org / 10.2307 / 3223958"]}

Key to the species of Canthocamptus for males (female characters indicated by asterisk) 1. Mandibular palp with 3 setae..................................................................... C. kunzi Apostolov, 1969 – Mandibular palp with 5 setae............................................................................................................ 2 2. P4 Enp2 with normal outer spine...................................................................................................... 3 – P4 Enp2 with modified finger-like outer spine................................................................................. 6 3. Habitus wide; P1 Enp1 reaching end of Exp2; anal somite with ventral processes......................... 4 – Habitus sub-cylindrical; P1 Enp1 reaching middle of Exp3; anal somite without ventral processes........................................................................................................................................................... 5 4. P5 eXopod with 6 setae; *caudal rami seta V of female conical.............................................................................................................................................................. C. verestschagini (Borutzky, 1931) – P5 eXopod with 5 setae; *caudal rami seta V of female long, normal......................................................................................................................................................... C. longifurcatus Borutzky, 1947 5. *Caudal rami seta IV of female normal........................................................ C. latus Borutzky, 1947 – *Caudal rami seta IV of female sickle-like, with bulb............................ C. bulbifer Borutzky, 1947 6. Anal somite with unguiform processes............................................................................................. 7 – Anal somite without processes....................................................................................................... 12 7. P3 Enp3 with 2 normal setae............................................................................................................ 8 – P3 Enp3 with vestigial or without setae........................................................................................... 9 8. Caudal rami setae IV and V with ʻhelle Stelleʼ........................... C. oregonensis M.S. Wilson, 1956 – Caudal rami setae IV and V without ʻhelle Stelleʼ.............................. C. staphylinus (Jurine, 1820) 9. P4 Enp2 with 2 normal inner setae................................................................................................. 10 – P4 Enp2 with 2 vestigial or without inner setae..............................................................................11 10. Caudal rami without inner spinules; *P5 eXopod of female without inner spinules.......................................................................................................................... C. microstaphylinus s. str. Wolf, 1905 – Caudal rami with inner spinules; *P5 eXopod of female with inner spinules................................................................................................................................ C. microstaphylinus monardi Roy, 1927 11. Distal edge of caudal rami with spinules............. C. macrosetifer Ishida in Ishida & Kikuchi, 1999 – Distal edge of caudal rami without spinules........ C. takkobuensis Ishida in Ishida & Kikuchi, 1999 12. P2 Enp2 with 5 setae....................................................................................................................... 13 – P2 Enp2 with 4 setae....................................................................................................................... 19 13. P3 Enp3 with vestigial seta............................................................................................................. 14 – P3 Enp3 with 2 normal setae.......................................................................................................... 15 14. Caudal rami with inner spinules; *P3 Enp3 of females with 5 setae................................................................................................................................ C. kitaurensis Kikuchi in Ishida & Kikuchi, 1999 – Caudal rami without inner spinules; *P3 Enp3 of females with 4 setae..................................................................................................................................................... C. carinatus Shen & Sung, 1973 15. P5 endopod inner seta/outer seta length>5.................................................... C. sinuus Coker, 1934 – P5 endopod inner seta/outer seta length C. glacialis Lilljeborg, 1902 – Anal operculum spinulose.............................................................................................................. 17 17. Caudal rami short (length to width ratio = 2)..................................... C. baikalensis Borutzky, 1931 – Caudal rami long (length to width ratio = 2.5)............................................................................... 18 18. Caudal rami seta V with ʻhelle Stelleʼ...................................................... C. iaponicus Brehm, 1927 – Caudal rami seta V without ʻhelle Stelleʼ.......................................... C. staphylinoides Pearse, 1905 19. Caudal rami very long (length to width ratio>3.5).................... C. robertcokeri M.S. Wilson, 1958 – Caudal rami of normal length (length to width ratio C. sinuus Coker, 1934 – Caudal rami without inner spinules; *P5 eXopod of females without inner spinules..................... 21 21. Spinular row of penultimate somite with gap; *caudal rami seta V of female without bulb................................................................................................................................... C. assimilis Kiefer, 1931 – Penultimate somite with circumsomitic spinular row; *caudal rami seta V of female with bulb................................................................................................................. C. waldemarschneideri sp. nov., Published as part of Novikov, Aleksandr & Sharafutdinova, Dayana, 2022, Revision of the genus Canthocamptus (Copepoda: Harpacticoida) with a description of a new species from the Lena River Delta (North-eastern Siberia), pp. 33-63 in European Journal of Taxonomy 826 (1) on pages 57-58, DOI: 10.5852/ejt.2022.826.1833, http://zenodo.org/record/6761616, {"references":["Apostolov A. 1969. Copepoda Harpacticoida von Bulgarien. Crustaceana. 16 (3): 311 - 320. https: // doi. org / 10.1163 / 156854069 X 00349","Borutzky E. V. 1931. Materialen zur Harpacticidenfauna des Baikalsees II. Zoologischer Anzeiger 93: 263 - 273.","Borutzky E. V. 1947. Materials on the fauna of Copepoda, Harpacticoida of Lake Baikal. Genus Canthocamptus Westwood. Doklady Akademii Nauk SSSR 58 (8): 1825 - 1828.","Wilson M. S. 1956. North American harpacticoid copepods: 1. Comments on the known fresh-water species of the Canthocamptidae. 2. Canthocamptus oregonensis, n. sp. from Oregon and California. Transactions of the American Microscopical Societ y 75 (3): 290 - 307. https: // doi. org / 10.2307 / 3223958","Ishida T. & Kikuchi Y. 1999. Canthocamptus iaponicus (Crustacea: Copepoda: Harpacticoida), and three new species of the genus from Japan. Species Diversity 4 (2): 339 - 352. https: // doi. org / 10.12782 / specdiv. 4.339","Shen C. & Sung T. 1973. The freshwater copepods from three provinces in northeastern China. Acta Zoologica Sinica 19: 35 - 42.","Coker R. E. 1934. Contribution to knowledge of North American freshwater harpacticoid copepod Crustacea. Journal of the Elisha Mitchell Scientific Society 50 (1 / 2): 75 - 141.","Lilljeborg W. 1902. Tres species novae generis Canthocampti e Novaja Semlja et Sibiria Boreali, sive Trenne nya Arter af Skaktet Canthocamptus fran Novaja Semlja och Norra Sibirien. Bihang till Kongliga Svenska Vetenskaps-akademiens Handlingar 28 (4): 9.","Wilson M. S. 1958. North American harpacticoid copepods 4. Diagnosis of new species of freshwater Canthocamptidae and Cletodidae (genus Huntemannia). Proceedings of the Biological Society of Washington 71 (1): 43 - 48.","Kiefer F. 1931. Kurze Diagnosen neuer Susswasser-Copepoden. Zoologischer Anzeiger 94 (5 / 8): 219 - 224."]}

The phylogenetic relationships of four dioecious populations and one parthenogenetic population of the harpacticoid Canthocamptus staphylinus (Jurine, 1820) were studied. Analysis of the mtCOI gene revealed two main clades as a phylogenetic tree and a network of haplotypes: a clade with Fennoscandian populations in Lake Paajarvi (Finland) and Lake Vanern (Sweden), and a second clade with populations in Lake Vortsjarv (Estonia), Orlov Pond in Saint Petersburg (Russia), and the type locality of the species in Lake Geneva (Switzerland). The parthenogenetic population of C. staphylinus showed the smallest nucleotide and haplotype polymorphisms and could have evolved as a reaction to the changing environmental conditions following the Last Glacial Maximum, 20K YBP.

External morphological and genetic structures of 94 individuals of Canthocamptus staphylinus Jurine (Harpacticoida, Copepoda, Crustacea) from ten European water bodies differing in type, including species type locality, have been analyzed. Significant distinctions of populations on six morphological features and morphometric indexes are established. The variability of both morphological and genetic markers is noted. As a result, two main species morph forms are allocated, typical and small. According to nucleotide, the variety of mitochondrial DNA harpacticoid specimens falls into ten haplotypes and three clades on the phylogenetic tree. One of them corresponds with the group isolated on morphological features (harpacticoids from the Sysola River basin, Komi Republic). The same-sex population from Lake Paajarvi (Finland), which is morphologically indistinguishable from the population from a type locality, is considerably divergent by nucleotide sequences of mtDNA. The role of geographical isolation and ecological factors in C. staphylinus microevolution is shown.

All six naupliar stages of the harpacticoid copepod Nitocra karanovici are described. A key to the identification of the naupliar stages is provided. Stages can be distinguished by number of segments of the exopod of antenna 2, setation of the limbs including the bud of the caudal ramus, and presence and setation of the bud of maxilla 1. A particular naupliar character was found in the nauplii of N. karanovici that is in common for all Ameiridimorpha, except Ameiridae and otherwise not known from other Harpacticoida. This is a pair of bean-shaped, bare medial cuticular areas of the ventral body wall present in Parastenocarididae, Cylindropsyllidae, and as in Canthocamptus, Attheyella, Moraria, and Mesochra of the Canthocamptidae.

Canthocamptus (Canthocamptus) staphylinus (Jurine, 1820) References and records from Norway Canthocamptus staphylinus (Jurine, 1820) ��� Sars (1863 a): 21; Sars (1911): 195 ��� 197. Sars (1863 a, 1911; see Table 1, supplementary material 1, for archive item Ms. Fol. 1109: 613) found this species to be very common in the neighbourhood of Oslo (Eastern Norway) and assumed it to be common also elsewere in the country. Archive item Ms. Fol 1109: 468, no. 64 (Table 1, supplementary material 1) gives a reference to records from Southern Norway. According to Sars, this species prefers shallow ponds and ditches and is less common in large lakes., Published as part of Dimante-Deimantovica, I., Jensen, T. C. & Walseng, B., 2016, Freshwater harpacticoids (Crustacea: Copepoda: Harpacticoida) in Norway ��� a comprehensive contribution from G. O. Sars, and a provisional checklist, pp. 1773-1795 in Journal of Natural History 50 (29) on page 8, DOI: 10.1080/00222933.2016.1159348, http://zenodo.org/record/269019

Data of more than 30 years about the harpacticoid copepods of the North-East of European Russia were used to investigate planktonic and benthic species in different types of water bodies. All 28 species and subspecies of harpacticoids known for the study region were found in summer. In spring, Attheyella nordenskjoldi nordenskjoldi and Moraria brevipes reproduced in the rivers and Canthocamptus staphylinus staphylinus bred in temporary water bodies. In the investigated river, the harpacticoid abundance was controlled primarily by water level, while in lentic habitats water temperature determined the formation of egg-sacs in females. Temperature conditions also influenced the speed and duration of ontogenesis. Timing of reproduction of the widespread and dominant species varied depending on temperature conditions for each area of the region under study.

WOS: 000327322500001, Troughs are one of the main components of villages in Turkey. They are constructed by converting springs or underground waters. Until now, there has been no extensive study investigating the composition and diversity of trough zooplankton species. In order to contribute knowledge on the zooplanktons in troughs, 142 troughs were randomly sampled from 17 districts in Ankara Province between 22 June and 3 July 2011. A total of 18 zooplanktons including 11 Copepoda and 7 Cladocera species were determined. Twelve of the 18 (Paracyclops chiltoni, Paracylops fimbriatus, Paracyclops imminutus, Tropocyclops prasinus, Diacyclops bisetosus, Acanthocyclops vernalis, Canthocamptus staphylinus, Attheyella crassa, Bryocamptus minutus, Macrothrix hirsuticornis, Oxyurella tenuicaudis, Moina macrocopa) are new records for Ankara. Paracyclops imminutus was reported for the third time in Turkey in the last 50 years. UPGMA illustrated 4 main clustering groups of species corresponding to some of their ecological characteristics. Poisson distribution analysis showed almost random distribution of species among the troughs (s(2)/mu = 1.04). With their cosmopolitan characteristics, 3 species (M. hirsuticornis, E. serrulatus, and C. sphaericus) are the most common species. Their ecological tolerance and optimum values were higher than the mean tolerances for different environmental variables. The results show that troughs may provide suitable conditions for zooplankton species.

The groundwater fauna, of which scarcely anything has previously been studied in formerly glaciated areas, was richest close to the water table and diminished markedly at greater depths. However, few individuals were generally recorded per 1 m 3 of water. Bryocamptus minutus was the most abundant species of copepod at an esker site, the other species recorded being Attheyella crassa , Bryocamptus pygmaeus , Moraria brevipes and Parastenocaris phyllura , and some species from the genus Diacyclops . At a shore bank infiltration site M. brevipes was the most numerous species. However, one esker site examined did not have any animals. Springs, which were grouped into those in a natural state and those under anthropogenic influence, had some species in common with esker groundwater, but also Paracyclops fimbriatus , Acanthocyclops robustus , Acanthocyclops vernalis , Diacyclops bicuspidatus , Megacyclops viridis , and the harpacticoid species Bryocamptus cuspidatus , Bryocamptus echinatus and Canthocamptus staphylinus . Of the spring copepods, P. fimbriatus appeared to withstand the influence of road de-icing with NaCl, but numbers of Moraria brevipes were reduced under this influence. Bryocamptus echinatus was more numerous in springs having a high oxygen content and high pH. The species found in esker groundwaters and springs were in part the same evidently cold-stenotherm species which inhabit the profundal zone of oligotrophic lakes.

Canthocamptus morimotoi Miura, a cave‐dwelling harpacticoid species belonging to C. mirabilis species group, is fully redescribed and illustrated on the basis of the material newly collected from the type locality, Simpigul Cave, South Korea. C. morimotoi is the only genuine subterranean species in the C. mirabilis group, and claimed to be a relict species restricted to its type locality. The sexually isomorphic ornamentation of the outer terminal seta on the distal exopodal segment of male leg 4 and the well‐developed spines on the disteromedial corner of anal somite are the most significant features differentiating this species from other members of the mirabilis‐group

Harpacticoids made up 19 and 30% of the meiobenthos proper by number and 39 and 55% by biomass at maximum depths and a depth of 20 m, respectively, in Lake Paijanne. Harpacticoids accounted for higher proportions of the total meiobenthos in oligotrophic and unpolluted areas than in polluted areas. Seven species were identified, with Canthocamptus staphylinus confined to semi-lotic areas influenced by organic pollution from a pulp mill. Other species exhibited somewhat different distributions in oligotrophic and mesotrophic areas. Harpacticoid densities were most closely correlated with oxygen content and phytoplankton biomass, and correlations with environmental values were closer at maximum depths than at 20 m. Attheyella crassa densities in the deepest zone had most marked negative correlation with total phosphorus, phytoplankton biomass, dissolved organic matter and organic sedimentation, while Paracamptus schmeili had the closest positive correlation with oxygen content. High densities of these species could be classified as an indicator of oligotrophic conditions. Similar correlations, although weaker, were evident for Bryocamptus minutus and still weaker for Bryocamptus echinatus and Moraria brevipes. Clustering of the stations based on harpacticoid abundances gave a similar result to clustering based on environmental data, particularly in the 20 m zone.

In phytotelmata of Jamaican bromeliads the harpacticoid copepods Epactophanes richardi Mrazek, 1893, Phyllognathopus viguieri (Maupas, 1892) and Attheyella (Canthosella) mervini sp. n. occurred. The new species conforms to the diagnosis of the subgenus, despite the fact that the endopods of legs 2–4 have retained more setae than in the species known for the Asian region. Attheyella (Canthosella) mervini lacks setae on the baseoendopod of leg 5, which is characteristic for neotropical Canthosella-species. We propose that Attheyella (Chappuisiella) kalima (Delachaux, 1924), Attheyella (Ch.) aliena Noodt, 1956, Elaphoidella siolii Kiefer, 1967, and Canthocamptus (Elaphoidella) striblingi Reid, 1990 be included in the subgenus Attheyella (Canthosella). Additionally, Attheyella (Chappuisiella) kalima of Dussart & Frutos, 1986 is included in this subgenus, but we propose the name Attheyella (Canthosella) pilagaensis sp.n., because the species as described differs from the original description of A. (C.) kalima (Delachaux, 1924).

There is presently, a substantial amount of information being gathered concerning the environmental risk associated with the perfluorooctanoic acid (PFOA) compound. The aim of this paper was to determine a 35 day community no observable effect concentration (NOEC(community)) or lowest observable effect concentration (LOEC) for freshwater zooplankton exposed to PFOA during a study in 30 l indoor aquatic microcosms. Some significant (P0.01) temporal fluctuations in zooplankton abundance were observed, however, a NOEC(community) could not be calculated. LOEC for various species varied between 10 and 70 mg l(-1). According to LOEC values, the tentative order of descriptors sensitivity was as follows: Daphnia magnarichnessor = Cyclops canthocamptus staphylinusCyclops diaptomustotal zooplanktonor = Rotifera sp. The long term ecological significance of these temporal fluctuations could not be determined in this study, however, the overall study cessation analysis showed that the structure of the ecosystem was changed from a more diverse community dominated by larger species towards a less diverse community dominated by smaller more and robust species (P0.05). Additional chronic toxicity testing should also be addressed since these compounds are so persistent and recalcitrant.

Benthic meiofauna was sampled at 19 stations, mainly in the northern part of Lake Ladoga, from depths between 13 and 199 m and from types of environment ranging from sheltered areas near pollution sources to less polluted open areas. About 80 taxa were identified, of these 70 to the species level. The greatest numbers of species were oligochaetes (24 species) and harpacticoids (8 species). Certain quantitative ratios of meiofauna were shown to be correlated with environmental data. The species of the oligochaete families Lumbriculidae and Aeolosomatidae and the harpacticoids as a collective group, excluding Canthocamptus staphylinus, were most clearly confined to the less eutrophied environments. The oligochaete species Amphichaeta leydigii, Dero digitata and Tubifex tubifex, the resting stages of Cyclopinae, and Eucyclops serrulatus among the Eucyclopinae were most clearly concentrated in the eutrophicated or polluted environments. The groups of Naididae, Cladocera and Eucyclopinae did not have much value as indicators. Shannon diversity index correlated positively with the total phosphorus content of the water, and number of species decreased with increasing depth. In general, it seems that the pollution tolerance of the meiofauna in a very large lake such as Lake Ladoga is high, presumably due to the effective mixing of water masses.

Organic loading and eutrophy is indicated at profundal depths by large numbers of resting copepodid stages of cyclopoid copepods, by the occurrence of the naidid oligochaete species, Amphichaeta leydigii and Specariajosinae, and the harpacticoid species Canthocamptus staphylinus, and by a low meiobenthos/ macrobenthos biomass ratio. An oligotrophic environment is indicated by the occurrence of the aeolo-somatid oligochaetes Aeolosoma quaternarium, A. hemprichi and Rheomorpha neiswestnovae, the naidid oligochaete Chaetogaster langi and the harpacticoid species Attheyella crassa and a high meiobenthos/ macrobenthos biomass ratio.

Elaphoidella moreae n. sp., Parapseudoleptomesochra hellenica n. sp. and Nitocrella achaiae n. sp. are described from phreatic subterranean waters of Greece. Moreover, new localities are reported for the species Elaphoidella karamani Chappuis, Elaphoidella elaphoides (Chappuis), Attheyella (Brehmiella) dentata (Poggenpol), Attheyella (Attheyella) crassa (Sars), Nitocrella skirensis Pesce, Nitocra spinipes Boeck, Bryocamptus (Bryocamptus) minutus (Claus), and Canthocamptus staphylinus (Jurine). The systematic status of the species Elaphoidella karamani, Elaphoidella eucharis Chappuis, and Elaphoidella elaphoides is briefly discussed.

Water quality standards are generally based on the effect of a single toxicant; unfortunately, the additive effects of a mixture of toxicants are never taken into account when fixing up water quality standards. This paper evaluates the additive effect of a mixture of toxicants on Canthocamptus (Crustacea spp). The results suggest that the toxicity of certain toxicants like phenol is increased when the poison is present in combination with heavy metals or other poisons. The results of this study point to the need for greater care when fixing up the permissible level of the toxicants; in all cases, the relevant agencies should take into consideration the additive effect of a mixture of toxicants.

Temporal and spatial differences in the abundance of dormant harpacticoid and cyclopoid copepods in a nearshore area of southeastern Lake Michigan are described. Core samples were taken at three depths (11, 17, and 23 m) at monthly intervals from May to November 1976–79. All dormant harpacticoids were Canthocamptus robertcokeri or Canthocamptus staphylinoides, and all dormant cyclopoids were stage IV copepodids, likely Diacyclops thomasi. The percentage of Canthocamptus and copepodids IVfound in the resting state declined dramatically with increased sampling depth. Dormant Canthocamptus were most abundant in late summer/fall in each of the four sampling years. During this period, usually over 50% of all Canthocamptus were found in the dormant condition. Dormant cyclopoids were most abundant between June and September, but exact seasonal patterns varied from year to year. Factors initiating the dormant condition are not clear, but water temperatures and day length may be important environmental cues. Some of the spatial and year-to-year differences in the proportion of dormant individuals appeared related to variations in the amount of surface detritus. This is the first report of a resting stage in the life cycle of cyclopoids in the Great Lakes.

Environmental conditions and Zooplankton abundance were recorded for eight months in common carp pond at Al‐Latifiyah (Baghdad), seasonal variations of some environmental factors such as water temperature, dissolved oxygen, pH, electrical conductance, chlorophyll a and light penitration were studied during the study period. Seasonal quantitative and qualitative of Zooplankton of the common carp (Cyprinus carpio) pond are reported, most of the genera were cladocerans (Scapholeberis kingi, Diaphanosoma brachyurum, Alona costata, Moina affinis, Side crystallina, Simocephalus vetulus. S. expinosus, Chydorus sphearicus) with copepods (Cyclops. Diaptomus, Canthocamptus) and Ostracoda (Cypria) second and thrid. Some of the genera were recorded through the study period but seasonally the highest number of species were found in April (ten species). Total number of species ranging fron 2 to 10 during sampling period.

The population dynamics of Canthocamptus staphylinus in the littoral zone of Lake Constance are described (fig. 2). Adult animals aestivate as cysts. The main part of the population emerges from the cysts in autumn. During the resting stage and the first spell after emerging, mortality is very low (fig. 3). Reproduction, expressed as numbers of ovigerous females, begins in November and reaches its maximum in January. The new generation becomes adult in May/June and encysts without previous reproduction. According to Sarvala (1979) it may be possible, that in littoral populations dormancy is induced by long day periods and temperatures of over 12° C (figs. 1, 2). In the profundal zone C. staphylinus also forms cysts, however, both light and temperature are not likely to induce this stage in depths of over 60 m.

A direct relationship existed between standing crops of zooplankton and distribution, growth, and feeding of young-of-the-year blueback herring, Alosa aestivalis, in the James River, Virginia. Zooplankton densities were highest upstream where food consumption and growth rates were correspondingly highest. A progressive downstream decrease and upstream increase in fish abundance occurred during the study. Condition (K) decreased after flooding from Hurricane Camille. Blueback herring fed primarily on copepods (Eurytemora affinis, Cyclops vernalis, and Canthocamptus robertcokeri), but cladocerans (Bosmina sp. and Diaphanosoma brachyurum) were also important. Selection (electivity) was strongest for adult copepods and weakest for copepod nauplii. Selection for copepodites and Bosmina sp. was moderate to weak. Feeding occurred only during daylight. Predation on copepods and copepodites by blueback herring resulted in population dominance by the smaller Bosmina sp. Respiration experiments were carried...

The harpacticoid copepod Canthocamptus staphylinus (Jurine) was shown to reproduce parthenogenetically in an oligotrophic Finnish lake. The population was univoltine with peaks of egg production in winter and early spring. Young from both peaks became adults in spring and aestivated as cysts. Laboratory experiments suggested that either high temperature (12 °C or more) or long days will inhibit egg production, but that both factors together are needed to induce encystment. Embryonic survival was low, on the average only 60%. The population was limited by low food levels in winter, and it is suggested that food shortage prevents the species from colonizing the profundal zone of oligotrophic lakes.

Field and laboratory observations show that the harpacticoid copepod, Canthocamptus staphylinus (Jurine) has a single generation in the year. There are two distinct phases in the annual cycle, a do...

Three freshwater crustacean larvae have been found to selectively degrade phenol, a common constituent of industrial waste discharges. The prospects of obtaining a low‐cost treatment system for replacing conventional methods for phenol‐containing waste waters look very promising. Though the proposed treatment is effective, care must be taken to dilute waste liquids before treatment with larvae.

Comparative phylogeography has become a powerful approach in exploring hidden or cryptic diversity within widespread species and understanding how historical and biogeographical factors shape the modern patterns of their distribution. Most comparative phylogeographic studies so far focus on terrestrial and vertebrate taxa, while aquatic invertebrates (and especially freshwater invertebrates) remain unstudied. In this article, we explore and compare the patterns of molecular diversity and phylogeographic structure of four widespread freshwater copepod crustaceans in European water bodies: the harpacticoids Attheyella crassa, Canthocamptus staphylinus and Nitokra hibernica, and the cyclopoid Eucyclops serrulatus, using sequence data from mtDNA COI and nuclear ITS/18S rRNA genes. The three taxa A. crassa, C. staphylinus and E. serrulatus each consist of deeply diverged clusters and are deemed to represent complexes of species with largely (but not completely) non-overlapping distributions, while in N. hibernica only little differentiation was found, which may however reflect the geographically more restricted sampling. However, the geographical patterns of subdivision differ. The divisions in A. crassa and E. serrulatus follow an east–west pattern in Northern Europe whereas that in C. staphylinus has more of a north–south pattern, with a distinct Fennoscandian clade. The deep mitochondrial splits among populations of A. crassa, C. staphylinus and E. serrulatus (model-corrected distances 26–36%) suggest that divergence of the lineages predate the Pleistocene glaciations. This study provides an insight into cryptic diversity and biogeographic distribution of freshwater copepods.

Acineta nitocrae, a suctorian ciliate previously known from Ukraine, was discovered in western Lake Erie in October 1997 and in the Detroit River in May 1999. Individuals were found inhabiting the body surface of Nitocra hibernica and N. incerta, nonindigenous harpacticoid copepods. Acineta nitocrae infested 64 % of N. hibernica in Lake Erie, whereas in Ukraine it infested between 24 and 80 % of N. hibernica populations. In Lake Erie, N. hibernica copepods suffered lower suctorian burdens than conspecific individuals in native habitats in Ukraine. In Ukraine, this suctorian was also found on two other harpacticoid species - Nitocra lacustris and Canthocamptus staphylinus. The highest preference of A. nitocrae was established for N. hibernica. Acineta nitocrae individuals from Lake Erie and Ukrainian populations of N. hibernica were similar with respect to dimensions of the lorica and stalk, but differed significantly in terms of the length and width of actinophores, with highest values observed for Lake Erie. Occurrence of A. nitocrae in the Great Lakes may be related to the introduction of its hosts, N. hibernica and N. incerta.

PROF. MEEK, in his letter to NATURE of Oct. 5 on “Adaptation”, has used in illustration of his views instances of crustacean races (of the amphipod Gammarus duebeni and the copepod Canthocamptus pygmcaeus) residing in pits and mines which had lost their colour and eyes without losing the power of reproducing those features on becoming once more acquainted with light. In Prof. Meek's opinion, more prolonged exposure to environmental strain might make this restoration more difficult by impairing the reversibility of the reaction, and he suggests that this sort of adaptation to life in the dark is ‘psychogenetic’ in origin. In addition to the many eyeless Crustacea of purely cavernous habit, Cyclops agilis Koch has been found underground with degenerate eyes, but the same and four other species of Cyclops as well as Canthocamptus staphylinus Jurine have often been found in the dark with normal eyes; loss of pigment has been observed in certain Ostracoda in similar situations (Moniez, Bull. biol. N. France, 1, P. 176; 1888).

The external morphology of Canthocamptus s.lat. and Fibulacamptus, gen. nov. has been resurveyed and a number of new terms and abbreviations introduced. Separate keys are given to the females and males of these genera and of all their 28 Australian species, as well as a table of their setal formulae and maps of their respective distributions; 21 of the 28 species are new. The genus Canthocamptus, when defined as in section 6 for reasons given in section 3, contains 24 species which can be placed in six fairly well-defined groups; however, the previous descriptions of Australian Canthocamptus species are so lacking in detail that two of them must be regarded as completely unidentifiable. C. bidens (which is probably parthenogenetic anyway), C. longipes and C. sublaevis are known so far only as females and Canthocamptus sp. 1 from only a single male, each of the others described here being from both sexes. C. ablatifurcatus, sp. nov. from New Caledonia is described in Appendix 4; but other existing descriptions of non-Australian species are not sufficiently detailed to refer any of them to one or other of the six groups, to equate any of these groups to a named genus or subgenus of the Canthocamptidae, or to offer any basis for the much-needed revision of this family. Fibulacarnptus differs from all other harpacticoids in the grapnel-like outer terminal seta on the male P4exopod3, but is otherwise close to Canthocamptus as defined here; it contains four species, all new.

PROF. LABBE, in a series of recent papers (C.R. Acad. Sci., Paris, 1924, t. 178, p. 132, 594; t. 179, p. 928; 1924, Arch. Zool. Exp., t. 62, p. 401), has communicated the results of observations made on the Salines of Croisic, and the conclusions he draws there from as to the nature and stability of species would, if substantiated, seriously shake the foundations of systematic zoology. For example, he asserts that, from the eggs of a parent form Canthocamptus minutus, O.F.M. exposed in the ovisac to the influence of a high PH, he has obtained a mixed progeny consisting of: (a) C. minutus (typical). (b) ‘Allomorph’ Mesochra (Walterstarffia) blanchardi Rich. (c) ‘Allomorph’ Canthocamptus lucidulus Rehb. (d) ‘Allomorph’ Mesochra salina n. sp.

ONE of the rarest of the freshwater species of the British Harpacticids is Canthocamptus bidens (Schmeil); but it has a very wide distribution abroad. However, until quite recently, the males had never been found either in the British Isles or abroad.