New insights into polyphyly of the harpacticoid genus Delavalia (Crustacea, Copepoda) through morphological and molecular study of an unprecedented diversity of sympatric species in a small South Korean bay Author Karanovic, Tomislav aranovic@utas.edu.au Author Kim, Kichoon text Zootaxa 2014 2014-03-25 3783 1 1 96 journal article 5789 10.11646/zootaxa.3783.1.1 414491b2-5167-4605-95ab-f679bf476618 1175-5326 4910562 E6155BDC-AEAE-475D-BC83-61B3B863344C Wellstenhelia clio sp. nov. ( Figs. 12–17 ) Type locality. South Korea , South Sea , Gwangyang Bay , sampling station 10, muddy sediments, 34.920944°N 127.785528°E ( Fig. 1 ) . Specimens examined. Female holotype dissected on one slide (collection number NIBRIV0000232676), male allotype dissected on one slide (collection number NIBRIV0000232677), two male paratypes and three female paratypes together on one SEM stub (collection number NIBRIV0000232678), six male paratypes and eight female paratypes and six copepodid paratypes together in ethanol (collection number NIBRIV0000232679), five females destroyed for DNA sequence (amplification unsuccessful); type locality, 18 February 2012 , leg. K. Kim. Two male paratypes and three female paratypes and one copepodid paratype together in ethanol (collection number NIBRIV0000232680), one female destroyed for DNA sequence (amplification successful, Code 0187), type locality, 30 July 2012 , leg. K. Kim. One female destroyed for DNA sequence (amplification unsuccessful), South Korea , South Sea , Gwangyang Bay , sampling station 15, muddy sediments, 34.890139°N 127.795111°E ( Fig. 1 ), 18 November 2012 , leg. K. Kim. Three males and three females destroyed for DNA sequence (amplification unsuccessful), South Korea , South Sea , Gwangyang Bay , sampling station 12, muddy sediments, 34.951389°N 127.734361°E ( Fig. 1 ), 18 November 2012 , leg. K. Kim. Etymology. The species is named after Clio (Ancient Greek: Κλειώ), one of nine Muses from Greek mythology, who was a patron of history. The species name is a noun in apposition (in the nominative case). Description. Female (based on holotype and two paratypes ). Body length from 540 to 617 µm (latter in holotype ). Body segmentation, colour, nauplius eye, hyaline fringes, integument thickness and surface appearence as in Wellstenhelia calliope sp. nov. , including minute sparse pits visible only on highest magnifications on scanning electron microscope. Most somite ornamentation also similar to Wellstenhelia calliope , and presumed homologous pores and sensilla numbered with same Arabic numerals (see Figs. 12A, B, C , 13A, B, C , 14A ) to allow easier comparison. Habitus ( Figs. 12A, B , 16A ) more robust, with prosome/urosome length ratio 1.2, body length/width ratio about 2.9, and cephalothorax nearly twice as wide as genital double-somite. Rostrum ( Figs. 12C , 16B ) slightly narrower in dorsal view than in Wellstenhelia calliope (arrowed in Fig. 12C ), but without any other difference in shape or ornamentation. Cephalothorax ( Figs. 12A, B, C , 13B , 16C ) about 0.8 times as long as wide; represents 28% of total body length. Surface of cephalothoracic shield ornamented as in Wellstenhelia calliope ; except two additional sensilla (nos. $, £) and one additional pore (no. ¥) present, two lateral pores (nos. 19, 33) missing, sensilla no. 40 paired, and somewhat different relative position of pores nos. 9, 10, 28 (arrowed in Figs. 12A, C ). Pleuron of second pedigerous somite ( Figs. 12A, B , 16D ) ornamented as in Wellstenhelia calliope , except lateral pair of sensilla no. 48 missing (arrowed in Fig. 12A ). Pleurons of third pedigerous somite ( Figs. 12A, B , 13C , 16D ), fourth pedigerous somite ( Figs. 12A, B , 14A , 16D ), and first urosomite ( Fig. 12A, B , 16E ) as in Wellstenhelia calliope . Genital double-somite ( Figs. 12A, B , 13A , 16E ) as in Wellstenhelia calliope , except anterior part even more inflated laterally, forming blunt chitinous processes, ventral pair of sensilla (no. 73) much more widely spaced, and two additional rows of minute spinules in anterior half (arrowed in Fig. 12B ). Last threeurosomites ( Figs. 12A, B , 13A , 16F ) as in Wellstenhelia calliope , except for short lateral rows of spinules on preanal somite, more widely spaced sensilla nos. 74 & 78, and more ventrally located pores 79 & 80. Caudal rami ( Figs. 12A, B , 13A , 16F ) short and stout, much shorter than in Wellstenhelia calliope (arrowed in Fig. 12A ), about 1.3 times as long as anal somite, cylindrical, 2.1 times as long as wide (ventral view), slightly divergent, and with space between them about one ramus width; ornamentation and armature as in Wellstenhelia calliope , except central part of inner margin without spinules and middle lateral seta much shorter (both arrowed in Fig. 13A ). FIGURE 12. Wellstenhelia clio sp. nov. , line drawings, female holotype: A, habitus, lateral view; B, habitus, dorsal view; C, rostrum, dissected and flattened, dorsal view; D, endopod of third swimming leg. Arabic numerals indicate sensilla and pores presumably homologous to those in Wellstenhelia calliope . Currency symbols ($, £, ¥) indicate unique sensilla and pores. Arrowheads point to most prominent specific features. Scale bars 100 µm. FIGURE 13. Wellstenhelia clio sp. nov. , line drawings, female holotype: A, abdomen, ventral view; B, left side of cephalothoracic shield, dissected and flattened; C pleuron of third pedigerous somite, dissected and flattened; D, mandibular palp, anterior view. Arabic numerals indicating sensilla and pores presumably homologous to those in Wellstenhelia calliope . Arrowheads pointing most prominent specific features. Scale bars 100 µm. FIGURE 14. Wellstenhelia clio sp. nov. , line drawings, A–D, female holotype, E–F, male allotype: A, pleuron of fourth pedigerous somite, dissected and flattened; B, fourth swimming leg without rami, anterior view; C, fifth leg, dissected and flattened, anterior view; D, sixth leg on genital somite, ventro-lateral view; E, cephalothoracic shield, lateral view; F, antennula, dorsal view. Arabic numerals indicating sensilla and pores presumably homologous to those in Wellstenhelia calliope . Currency symbols ($, £, €) indicating unique sensilla and pores. Arrowheads pointing most prominent specific features. Scale bars 100 µm. FIGURE 15. Wellstenhelia clio sp. nov. , line drawings, male allotype: A, urosome, ventral view; B, urosome, lateral view; C, pleuron of second pedigerous somite, dissected and flattened. Arabic numerals and hash mark (#) indicate sensilla and pores presumably homologous to those in Wellstenhelia calliope . Arrowheads point to most prominent specific features. Scale bars 100 µm. FIGURE 16. Wellstenhelia clio sp. nov. , scanning electron micrographs, female paratype: A, habitus, dorsal view; B, rostrum, dorsal view; C, cephalothorax, dorsal view; D, pedigerous somites, dorsal view; E, first urosomite and genital double-somite, dorsal view; F, anal somite and caudal rami, dorsal view. Scale bars 40 µm (B), 50 µm (D, E, F), 100 µm (C), and 200 µm (A). Antennula ( Fig. 16A ), antenna, labrum, paragnaths, mandibula ( Fig. 13D ), maxillula, maxilla, and maxilliped as in Wellstenhelia calliope . Swimming legs ( Figs. 12D , 14B ) segmentation, ornamentation, armature, and even proportions of various armature elements as in Wellstenhelia calliope , except proximal rows of spinules on coxae slightly longer (arrowed in Fig. 14B ) and first endopodal segments without anterior pore (arrowed in Fig. 12D ). Fifth leg ( Figs. 12A , 14C ) segmentation, general shape, number of armature elements, and most ornamentation as in Wellstenhelia calliope , except innermost endopodal seta proportionately longer (arrowed in Figs. 12A , 14C ), space between two central endopodal setae wider (arrowed in Fig. 14C ), exopod wider at base (arrowed in Fig. 14C ), and additional pore present on anterior surface of exopod (arrowed in Fig. 14C ). Length ratio of endopodal setae, starting from inner side, 1: 1.2: 1.7: 1. Length ratio of exopodal setae, starting from inner side, 1: 0.3: 0.3: 0.8: 0.6: 0.6. Sixth leg ( Fig. 14D ) as in Wellstenhelia calliope . Male (based on allotype and five paratypes ). Body length from 519 to 564 µm ( 555 µm in allotype ). Habitus ( Fig. 17A ), colour, rostrum ( Fig. 17C ), shape and almost all ornamentation of cephalothorax ( Figs. 14E , 17A, C ), shape and ornamentation of second pedigerous somite ( Figs. 15C , 17A ) (including missing sensilla pair no. 48; arrowed in Fig. 15C ), third pedigerous somite ( Fig. 17A ), and fourth pedigerous somite ( Fig. 17A ), ornamentation of first urosomite ( Figs. 15B , 17B ), ornamentation of last threeurosomites ( Figs. 15A, B , 17A, B ), caudal rami ( Fig. 15A, B , 17A ), antenna ( Fig. 17D ), labrum ( Fig. 17D ), paragnaths, mandibula, maxillula, maxilla ( Fig. 17E ), maxilliped ( Fig. 17E ), first swimming leg ( Fig. 17F ), and coxae, bases, and exopods of second, third, and fourth swimming legs as in female. Prosome/urosome ratio 1.1, greatest width at posterior end of cephalothorax, body length/width ratio about 3.5; cephalothorax twice as wide as genital somite in dorsal view. Genital somite and third urosomite not fused. Cephalothorax ( Figs. 14E , 17A, C ) in addition to all sensilla and pores present in female, with one additional pair of lateral pores in posterior half (no. €). First urosomite ( Figs. 15B , 17B ) slightly narrower and longer than in female but also with three pairs of sensilla (nos. 64, 65, 66) and two pairs of pores (nos. 63, 67). Genital somite ( Figs. 15A, B , 17B ) somewhat wider and with fewer spinules than in Wellstenhelia calliope , but with all ornamentation same, except pore no. 68 situated more ventrally (arrowed in Fig. 15B ), i.e. much closer to pore no. #, and in one paratype two pores extremely close to each other ( Fig. 17B ). Third urosomite ( Figs. 15A, B , 17B ) as in Wellstenhelia calliope , except ventral row of spinules not interrupted between sensilla pair no. 73 and not broken between sensilla nos. 72 & 73 (both arrowed in Fig. 15A ). Antennula ( Figs. 14F , 17C ) shape, segmentation, armature, and most ornamentation as in Wellstenhelia calliope , except spiniform process on first segment smaller (arrowed in Fig. 15F ), dorsal pore missing (arrowed in Fig. 15F ), and aesthetascs on third and fourth segments longer. Fifth leg ( Figs. 15A, B , 17B ) shape, armature, and ornamentation as in Wellstenhelia calliope , except for shallow ventral notch on fused baseoendopods. Sixth legs ( Fig. 15A, B , 17B ) as in Wellstenhelia calliope , except middle seta proportionately shorter (arrowed in Fig. 15B ). Variability. Most morphological features are extremely conservative, including the sensilla and pores pattern of somites, and length ratio of different armature on appendages. Except for body length, the only other variable feature was the position of lateral pore no. 68 on the male genital somite (arrowed in Fig. 15B ). Morphological affinities. Wellstenhelia clio sp. nov. has no obvious autapomorphy that would distinguish it at once from all other congeners. As mentioned above, its female fifth leg ( Fig. 14C ) is relatively similar to that in the Swedish Wellstenhelia hanstromi ( Lang, 1948 ) comb. nov. , with two inner endopodal setae of about the same length and strength and as long as the outermost endopodal seta (see Lang 1948 ), although not as long as those in the Artcic Wellstenhelia melpomene sp. nov. (see Kornev & Chertoprud 2008 ). However, this may be a plesiomorphic character, as a similar fifth leg endopod can be found in several lineages of the genus Delavalia Brady, 1869 . Unfortunately, both Wellstenhelia hanstromi and Wellstenhelia melpomene are known so far only from a very limited set of female morphological characters ( Lang 1948 ; Kornev & Chertoprud 2008 ) and most features cannot be compared. Even so, there is no doubt that all three represent separate species, as Wellstenhelia hanstromi has much longer caudal rami and a shorter seta on the first endopodal segment of the fourth leg than the other two, and Wellstenhelia melpomene has a longer exopod and all setae on the fifth leg, while Wellstenhelia clio has a shorter endopod of the first leg. In the absence of other evidence we have to assume that Wellstenhelia clio is probably morphologically most similar to Wellstenhelia melpomene , as these two species also have very similar caudal rami. Other congeners can be easily distinguished from Wellstenhelia clio by many characters. Wellstenhelia calliope sp. nov. and Wellstenhelia qingdaoensis ( Ma & Li, 2011 ) comb. nov. have much longer caudal rami and a shorter innermost seta on the female fifth leg endopod; Wellstenhelia euterpe sp. nov has much shorter caudal rami and only three setae on the female fifth leg endopod; while Wellstenhelia erato sp. nov. and Wellstenhelia bocqueti ( Soyer, 1971 ) comb. nov. have a much shorter innermost seta on the female fifth leg endopod. Each species can additionally be distinguished from Wellstenhelia clio by some other feature in the proportion of armature elements or ornamentation of somites. Numerous differences between this species and Wellstenhelia calliope are indicated by arrowheads in Figs. 12A, B, C, D , 13A , 14B, C, F , 15A, B, C .