Idya furcata, Karanovic & Lee, 2016

Karanovic, Tomislav & Lee, Wonchoel, 2016, First records of Hemicyclops tanakai Itoh and Nishida, 2002 and Tisbe ensifer Fischer, 1860 (Crustacea, Copepoda) in Korea, Journal of Species Research 5 (3), pp. 289-299 : 291-293

Tisbe cf. ensifer Fisher, 1860 ( Figs. 4 , 5 )

Synonymy. Tisbe ensifer Fisch. ­ Fisher (1860), p. 668, figs. 67­70; Idya furcata n. sp. ­ Brady (1880), p. 172, plate 67, fig. 9; Idya ensifera (Fischer) ­ Grandori (1912), p. 21; Pesta (1920), p. 584, fig. K24; Sars (1905), p. 90, plate 53, fig. 1; Idyaea ensifera (Fischer) ­ Sars (1909), p. 21; Pesta (1927), p. 45; Lang (1934), p. 1, figs. 3-4; Idyaea ensifera var. indica n. var. ­ Sewell (1924), p. 817, plate 52, fig. 1; Tisbe ensifera var. indica (Sewell) ­ Sewell (1940), p. 160; Tisbe ensifera Fischer ­ Gestraecker (1878), p. 799; Gurney (1927), p. 497; Willey (1930), p. 83; Tisbe ensifer Fischer ­ Lang (1948), p. 372, fig. 165/1; Chislenko (1967), p. 525, fig. 27; Kornev and Chertoprud (2008), p. 106, fig. 5/38/A, B. [non] Tisbe ensifera (Fischer) ­ Chiba (1956), p. 65, fig. 63.

Type locality. Portugal, Madeira Island , ponds and wet washed seaweed on sandy beaches, approximately 32°39 ′

N 16°54′W.

Specimens examined. Two females dissected on one slide each (ovigerous NIBR IV 0000287269 , non­ovigerous NIBR IV 0000287270 ); both collected from Korea, Sokcho , new boat harbor, shallow littoral, 23 September 2011, leg. T. Karanovic. 38°10.134′N 128°36.512′E .

Diagnosis. Body length, excluding caudal setae, from 780 to 845 μm. Habitus ( Fig. 4A ) robust, dorsoventrally compressed, with prosome/urosome ratio about 1.8, and greatest width at posterior end of cephalothorax. Prosome ovoid, about 1.7 times as long as wide, 2.3 times as wide as genital double­somite. Urosome ( Fig. 4B ) gradually tapering posteriorly, genital double­somite 0.9 times as long as wide, 1.6 times as wide as anal somite, only slightly expanded in anterior half, with central subdivision suture along dorsal and lateral surfaces. Genital operculum ( Fig. 4C ) covered with extremely reduced sixth leg. Caudal rami ( Fig. 4B ) half as long as wide. Atennula ( Fig. 4D ) eight­segmented, with the proportion of segmental lengths (proximal to distal) 1: 2.9: 3.1: 1.8: 0.6: 0.6: 0.5: 1.6, and armature formula 1.14.9.4 + ae.2.8.6 + ae. Antenna ( Fig. 4E ) with minute unarmed coxa, large basis with single seta, two­segment­ ed robust endopod with one seta on first segment and nine elements (including four geniculated), and four segmented slender exopod with armature formula 1.1.1.3. Labrum ( Fig. 4F ) trapezoidal, with narrow and straight cutting edge ornamented with continuous row of strong spinules. Mandibula ( Fig. 5A ) with narrow cutting edge on coxal gnathobase, armed with three complex teeth in ventral part, four simple teeth in dorsal part, and single dorsalmost unipinnate seta. Maxilla ( Fig. 5B ) with single minute endite on large syncoxa bearing two smooth setae, allobasis drawn out into strong arched claw with one short spiniform seta in proximal third. Maxilliped ( Fig. 5C ) prehensile and slender, basis 3.8 times as long as wide, 2.5 times as long as syncoxa, and 1.1 times as long as apical claw on minute endopod. All swimming legs ( Fig. 5 D­F) with three­segmented endopods and exopods. First swimming leg ( Fig. 5D ) with strong inner basal spine and all segments of different lengths, first endopodal segment 2.5 times as long as wide, slightly shorter than second endopodal but much wider, about as long as first two exopodal segments combined, with single long inner seta, second endopodal segment 3.8 times as long as wide, almost nine times as long as third endopodal segment, with single inner seta, third endopodal segment minute, as long as wide, with one minute slender seta and two comb-like short spines, first exopodal segment 1.8 times as long as wide, with single large outer spine, second exopodal segment 1.7 times as long as wide, twice as long as first exopodal segment and 2.6 times as long as third exopodal segment, with short out­ er spine and short inner seta, third exopodal segment 0.8 times as long as wide, with five comb­like spines and two long setae. Second to fourth legs ( Fig. 5E, F ) similar to each other, with first and second endopodal and exopodal segments of similar size and slightly larger third exopodal and exopodal segments, first and second exopodal segments with one outer spine and one inner seta, first endopodal segment with single inner seta, second endopodal segment with two inner setae, spine/seta formula of third exopodal segments 4.4.4/3.4.4, spine/seta formula of third endopodal segments 1.1.1/4.5.4. Fifth leg with three setae on short endopodal lobe, exopod about 7.5 times as long as wide, with five setae in distal part.

Figures

Fig. 4. Tisbe cf. ensifer Fischer, 1860 from Korea, female. A. ovigerous (top) and non­ovigerous (bottom) female habitus. B. urosome. C. genital field, with reduced sixth legs. D. antennule. E. antenna and labrum. F. labrum.

Fig. 5. Tisbe cf. ensifer Fischer, 1860 from Korea, female. A. coxal gnathobase of mandibula. B. maxilla. C. maxilliped. D. first swimming leg. E. second swimming leg with last two exopodal segments broken off. F. third swimming leg.