Hatschekia kabatai, Uyeno, Daisuke & Nagasawa, Kazuya, 2010

Uyeno, Daisuke & Nagasawa, Kazuya, 2010, The copepod genus Hatschekia Poche, 1902 (Siphonostomatoida: Hatschekiidae) from triggerfishes (Pisces: Tetraodontiformes: Balistidae) from off the Ryukyu Islands, Japan, with descriptions of eleven new species, Zootaxa 2478, pp. 1-40 : 10-13

Hatschekia kabatai n. sp.

( Figs 30–44 )

Type material. Holotype, female ( NSMT –Cr 20903), ex Xanthichthys lineopunctatus (Hollard) ( Tetraodontiformes : Balistidae ), off Izena-jima Island (26°55’N, 127°54’E), the Ryukyu Islands, East China Sea, Japan, 10 April 2008. Paratypes: 3 females ( NSMT –Cr 20904), ex X. lineopunctatus , off Izena-jima Island (26°55’N, 127°54’E), the Ryukyu Islands, East China Sea, Japan, 10 April 2008; 3 females ( RUMF – ZC–00923), ex X. lineopunctatus , off Izena-jima Island (26°55’N, 127°54’E), the Ryukyu Islands, East China Sea, Japan, 10 April 2008.

Description of female. Body ( Figs 30–31 ) 876–946 (912 ± 31) long, excluding caudal rami (n = 7). Cephalothorax ellipsoidal, slightly shorter than wide [252–285 (267 ± 10) ×313–360 (333 ± 17)], with dorsal, M-shaped chitinous frame with mid-line bifurcated at posterior end. Trunk bearing posterior lobes, longer than wide [639–772 (680 ± 46) × 233–331 (271 ± 34)], widest in anterior ¼. Urosome ( Fig. 32 ) excluding caudal ramus shorter than wide [31–46 (37 ±) × 67–87 (76 ± 7)], with constriction in middle. Genital complex fused to abdomen without border. Caudal ramus ( Fig. 32 ) slightly longer than wide [18–21 (20 ± 1) × 9–15 (13 ± 2)], bearing 5 naked setae.

Rostrum expanded anterior to cephalothorax with 1 digitiform process on posterolateral corners ( Fig. 33 ). Antennule ( Fig. 33 ) indistinctly 5-segmented, 150–245 (220 ± 33) long; armature formula: 10, 5, 4, 1, 13 + 1 aesthetasc. Antenna ( Fig. 34 ) 3-segmented; proximal segment (coxa) unarmed; middle segment (basis) ornamented with surface pits; terminal claw with 1 basal seta; proximal segment length 67–83 (76 ± 5); middle segment length 144–201 (167 ± 18); terminal claw length 34–70 (42 ± 13); total length 258–345 (284 ± 29). Parabasal papilla ( Fig. 35 ) well developed, wrinkled. Oral cone robust. Mandible ( Fig. 36 ) slender, with 5 sharp apical teeth. Maxillule ( Fig. 37 ) bilobate; both lobes armed with 2 tapering elements; inner lobe bearing swollen inner element. Maxilla ( Fig. 38 ) 4-segmented; proximal segment unarmed; second segment rod-like, with 1 basal seta; third segment elongate, with 1 distal seta; terminal segment small, with 1 small seta and bifid claw. Maxilliped absent.

Legs 1 and 2 ( Figs 39–40 ) biramous, with both exopods composed of 2 indistinct segments and 2– segmented endopods; both rami bearing blunt setae; leg armature formula as follows:

Leg 1 ( Fig. 39 ) 103–120 (112 ± 8) long; protopod length 52–71 (63 ± 7); exopod length 46–51 (49 ± 2); endopod length 26–38 (32 ± 4). Leg 2 ( Fig. 40 ) length 106–139 (117 ± 11); protopod length 61–88 (70 ± 9); exopod length 37–54 (47 ± 6); endopod length 51–57 (53 ± 2). Both exopods and protopods of leg 2 ornamented with rows of blunt spinules on anterior surface.

Intercoxal sclerites of legs 1 and 2 ( Figs 41–42 ) bear 2 short processes and 2 long, wrinkled processes.

Leg 3 ( Fig. 43 ) represented by 2 simple setae originating on anterior mid-lateral surface of trunk. Leg 4 ( Fig. 44 ) represented by 1 simple lateral seta on posterior ¾ of trunk.

Attachment site. Gill filaments.

Remarks. Hatschekia kabatai n. sp. also has 4 processes on the intercoxal sclerites of legs 1 and 2, a character shared with 10 species (see remarks of H. hemicyclium ) and 2 new species, i.e. H. hemicyclium n. sp. and H. jonesi n. sp. The new species has blunt setae on legs 1 and 2 a character not share with the abovementioned 12 congeners which typically have acutely pointed setae. Furthermore, H. balistae differs from the new species by the presence of an apex on the cephalothorax. The 10 setae on the proximal segment of the antennule present in the new species. is shared with 3 species (i.e. H. lima , H. pseudostracii and H. sunaoi ). Howeve, the new species can be distinguished from these congeners by the presence of posterior lobes on its trunk.

Etymology. The specific name of the new species, kabatai , is dedicated to Dr. Z. Kabata, an outstanding copepodologist who has made great advances in the systematics and phylogeny of the parasitic copepods.

Figures

FIGURES 30 – 38. Hatschekia kabatai n. sp., female, holotype NSMT – Cr 20903. 30, habitus dorsal; 31, habitus dorsal with egg sacs; 32, posterior part of trunk, dorsal; 33, antennule, ventral, rp = rostrum process; 34, antenna, ventral; 35, antenna with parabasal papilla (drawn from a paratype, NSMT – Cr 20904); 36, mandible; 37, maxillule; 38, maxilla. Scale bars: 30, 34 – 35, 100 μm; 31, 200 μm; 32 – 33, 38, 40 μm; 36 – 37, 20 μm.

FIGURES 39 – 44. Hatschekia kabatai n. sp., female, holotype NSMT – Cr 20903. 39, leg 1, anterior view; 40, leg 2, anterior view; 41, intercoxal sclerite of leg 1, anterior view; 42, intercoxal sclerite of leg 2, anterior view; 43, leg 3; 44, leg 4. Scale bars: 39 – 42, 40 μm; 43 – 44, 10 μm.