Cepolacanthus kimi, Maran, Balu Alagar Venmathi, Moon, Seong Yong, Adday, Thamir Katea & Tang, Danny, 2016

Maran, Balu Alagar Venmathi, Moon, Seong Yong, Adday, Thamir Katea & Tang, Danny, 2016, Cepolacanthus kimi, a new genus and species of copepod (Cyclopoida: Taeniacanthidae) parasitic on Bandfish Acanthocepola abbreviata (Valenciennes, 1835) (Actinopterygii: Cepolidae) caught off the Iraqi coast, Zootaxa 4174 (1), pp. 249-258 : 252-256

Cepolacanthus kimi sp. nov.

( Figs. 1‒19 )

Type material. Holotype female (NIBRIV0000306931) and paratype adult female (dissected and mounted on one glass slide) (NIBRIV0000306932), collected from the gills of a single specimen of Acanthocepola abbreviata captured off the fishing port of Al-Faw City , Basrah Province, Iraq, 21 July 2011 .

Adult female. Body ( Fig. 1 ) elongated, 1.37‒1.51 mm (mean = 1.44, n = 2) long (excluding caudal setae) and 0.31–0.36 mm wide (mean = 0.34). Prosome composed of broad subcircular cephalothorax (first pedigerous somite fused with cephalosome) and narrower free second to fourth pedigerous somites; fourth pedigerous somite twice as long as two preceding somites. Urosome nearly as long as prosome and composed of fifth pedigerous somite, genital somite, and three free, successively longer abdominal somites. Genital somite ( Fig. 2 ) 1.77 times wider (169 µm) than long (95 µm). Abdomen long (0.59 mm), with proportional lengths (%) between first to third abdominal somites 26.1: 33.5: 40.4; all abdominal somites naked. Caudal ramus ( Fig. 3 ) 3.16 times longer (98 µm) than wide (31 µm), bearing seven setae; setae I, II, III and VII naked; setae IV and V with bristles along both margins; seta VI with medial row of spinules; seta VI (37 µm) about 1.32 times as long as seta VII (28 µm); seta V (153 µm) longest, about 2.94 times as long as seta IV (52 µm).

Rostrum ( Fig. 4 ) well developed, reflexed ventrally and bearing one frontal pair of sensilla; ventral area of rostrum with longitudinal sclerotized structure bearing mid-lateral bulge. Antennule ( Fig. 5 ) 6-segmented (articulation between ancestral segments XIV–XVII and XVIII–XX not expressed), with armature formula 5, 15, 8, 4, 2 + 1 aesthetasc and 7 + 1 aesthetasc. Antenna ( Fig. 6 ) composed of coxobasis and two endopodal segments; coxobasis with inner distal naked seta; first endopodal segment with naked seta on inner central surface; second endopodal segment bearing two unequal pectinate processes (each with row of spinules), three claw-like spines and five unequal setae (four naked; one pinnate). Postantennary process ( Fig. 7 ) elongated, curved distally.

Labrum ( Fig. 8 ) broad, with row of minute spinules along rounded posterior margin. Mandible ( Fig. 9 ) 1- segmented, armed with two apical blades and bristled accessory seta; outer blade twice length of inner blade and spinulate along inner margin; inner blade spinulate along both margins. Paragnath ( Fig. 10 ) digitiform, bearing tuft of minute setules proximally and one midventral and one distal patch of minute spinules. Maxillule ( Fig. 11 ) lobate, with knob-like process anteriorly and two long bristled setae (outer 89 µm, inner 68 µm) and three short naked setae. Maxilla ( Fig. 12 ) 2-segmented; syncoxa robust, naked; basis represented by serrated terminal process armed with long spinulated spine and minute naked seta; latter situated more proximally on terminal process than spinulated spine. Maxilliped ( Fig. 13 ) 3-segmented; syncoxa robust, irregularly-shaped, bearing minute naked seta on anteroventral margin; basis elongate, with two mid-medial naked setae; terminal claw (endopod) long and attenuate, bearing two unequal naked setae proximally and row of teeth along inner distal margin.

Legs 1–4 biramous ( Figs. 14‒18 ); leg 1 with 2-segmented rami; legs 2–4 with 3-segmented exopod and 2- segmented endopod. Armature on rami of legs 1‒4 as follows (Roman numerals = spines; Arabic numerals = setae; int. = intermediate spine):

Leg 1 ( Fig. 14 ) coxa, basis and rami flattened; intercoxal sclerite subtriangular, ornamented with fine spinules on anterodistal surface; coxa with minute spinules along distolateral margin; basis ornamented with patch of setules on outer border and row of minute spinules at insertion of endopod. Leg 2 ( Fig. 15 ) intercoxal sclerite triangular, ornamented with two patches of spinules along posterior margin; coxa with two short rows of minute spinules along posterior margin; basis with minute spinules near insertion point of each ramus; exopodal spines spinulate along outer margin, each with accessory terminal flagellum; outer margin of exopodal segments ornamented with row of spinules; endopodal segments with row of setules along lateral margin; second endopodal segment also with minute spinules at base of each spinulate spine. Legs 3 ( Fig. 16 ) and 4 ( Fig. 17 ) similar to leg 2, except intercoxal sclerite much wider than long, each furnished with spinulate patch on posterolateral corners, and terminal exopodal segment of leg 4 ( Fig. 18 ) with large, outer subapical protuberance bearing fine apical spinules.

Leg 5 ( Fig. 19 ) well developed, 2-segmented, 1.81 times longer (58 µm) than wide (32 µm). Protopodal segment unornamented and armed with dorsolateral pinnate seta. Free exopodal segment ornamented with row of spinules on both margins and at base of each spine, and armed with two spinulated spines, one naked spine and one long naked seta. Leg 6 ( Fig. 2 ) vestigial, represented by opercular plate armed with three naked setae at egg sac attachment area on genital somite.

Adult male. Unknown.

Attachment site. Gills.

Etymology. The species is named in honor of Prof. Il-Hoi Kim (Gangneung-Wonju National University, South Korea), a world-renowned parasitic copepod expert.

Figures

FIGURES 1 – 6. Cepolacanthus kimi gen. et sp. nov. (female). 1, habitus, dorsal; 2, genital and first abdominal somites, dorsal; 3, caudal rami (seta I indicated by arrows), dorsal; 4, rostral area, ventral; 5, antennule, ventral; 6, antenna, dorsal. Scale bars: 1 = 200 µm; 2 – 6 = 50 µm.

FIGURES 7 – 13. Cepolacanthus kimi gen. et sp. nov. (female). 7, postantennal process, ventral; 8, labrum, ventral; 9, mandible, ventral; 10, paragnath, ventral; 11, maxillule, ventral; 12, maxilla, ventral; 13, maxilliped, ventral. Scale bars: 5 0 µm.

FIGURES 14 – 19. Cepolacanthus kimi gen. et sp. nov. (female). 14, leg 1, anterior; 15, leg 2, anterior; 16, leg 3, anterior; 17, leg 4, anterior; 18, distal exopodal segment of leg 4, anterior; 19, leg 5, anterior. Scale bars: 14 – 17, 19 = 50 µm; 18 = 25 µm.