Chondracanthid copepods parasitic on flatfishes of Kerala, India Author Ju-Shey text Journal of Natural History 2000 2000-05-30 34 5 709 735 http://dx.doi.org/10.1080/002229300299372 journal article 10.1080/002229300299372 1464-5262 Bactrochondria papilla sp. nov. (®gures 3±4) Material examined. Twenty-seven adult mm (each with attached l) found on gill ®laments of Cynoglossus dubius (Regan) : eight collected on 14.ii.1994 and 19 collected on 20 July 1994 . Holotype ( USNM 285492 ) and ten paratypes ( USNM 285493 ) have been deposited in the US National Museum of Natural History , Smithsonian Institution , Washington , DC, and the remaining paratypes and other specimens kept in the author’s (IHK) collection. Female. Body (®gure 3A) greatly elongated and cylindrical, 2.52±4.56 mm long and 0.37±0.52 mm wide. Head (®gure 3B) longer than wide, 0.60Ö 0.37 mm (not including ināted antennule), with prominent cephalic process (a swollen base tipped with a nipple-like protrusion) at each anterolateral corner (®gures 3C, F). Neck region formed by ®rst pediger, remaining prosomal somites fused into a long, cylindrical trunk. Genital double somite indistinguishably fused to trunk (®gures 3A,D), carrying a central vermiform process on ventral side. Abdomen like a narrow ring attached to genital double somite (®gure 3D). Caudal ramus (®gure 3D) a pointed spiniform process carrying three setae and one tubercle. Longest egg sac 8.64 mm long, nearly twice as long as its body length. Antennule (®gure 3E) with ināted base and cylindrical tip; armature being (from proximal to distal) 1-1-2-1-7. Antenna (®gure 3F) two-segmented; terminal segment an uncinate hook. Labrum (®gure 3G) with smooth posterior margin. Mandible (®gure 3H) two-segmented; terminal blade with 21 to 27 teeth on convex (inner) side and 12 to 16 teeth on convex (outer) side. Maxillule (®gure 3I) with three blunt, terminal setae. Maxilla (®gure 3J) two-segmented; ®rst segment robust but unarmed; second segment bearing one small, simple, basal seta, one large seta with hyaline tip and a row of seven to nine teeth along inner edge of terminal process. Maxilliped (®gure 4A) three-segmented; ®rst segment largest but unarmed, second segment expanded distally with enlarged inner corner armed with two patches of denticles, and terminal segment reduced to a small claw attached to non-swollen outer distal corner of second segment. Leg 1 (®gure 4B) with greatly enlarged, process-like protopod carrying an outer basal seta and much reduced, knob-like rami. Endopod unarmed, but exopod tipped with ®ve short setae, four terminal and one subterminal. Leg 2 (®gure 4C) biramous; protopod largely fused to trunk and only identi®able by its outer, basal seta. Both rami rod-like, with exopod larger than endopod and tipped with four short setae, three terminal and one subterminal. FIG. 3. Bactrochondria papilla gen. et sp. nov. Female: (A) habitus of adult, dorsal; (B) head and neck, dorsal; (C) same, lateral; (D) genito±abdomen, ventral; (E) antennule; (F) antenna; (G) labrum; (H) mandible; (I) manxillule; (J) maxilla. Scale bars: 0.2 mm in (A); 0.1 mm in (B±D); 0.05 mm in (E, F); 0.02 mm in (G±J). FIG. 4. Bactrochondria papilla gen. et sp. nov. Female: (A) maxilliped; (B) leg 1; (C) leg 2. Male: (D) habitus of adult, lateral; (E) genito±abdomen, ventral; (F) antennule; (G) antenna; (H) mandible; (I) paragnath; (J) maxillule; (K) maxilla; (L) maxilliped, posterior; (M) maxilliped, anterior; (N) leg 1; (O) leg 2. Scale bars: 0.05 mm in (A); 0.1 mm in (B, D); 0.02 mm in (C, E); 0.01 mm in (F±O). Male. Body (®gure 4D) 388 m m long, cephalosome moderately swollen. Genital somite (®gure 4E) with prominent ventrolateral ridges but abdomen small and indistinct. Caudal ramus (®gure 4E) a spiniform process bearing a medial seta and a ventral tubercle at base. Antennule (®gure 4F) elongate and cylindrical, with terminal portion set oOE in a posteroventrally directed knob; armature being 1-1-1- 2-8. Antenna (®gure 4G) a strongly recurved hook bearing an inner setule. Mandible (®gure 4H) with fewer teeth on terminal blade, 14 on convex side and seven to eight or concave side. Paragnath (®gure 4I) a spinulose lobe. Maxillule (®gure 4J) with two terminal elements. Maxilla (®gure 4K) with seven teeth on inner surface of terminal process. Maxilliped (®gure 4L) with much reduced, terminal claw visible in lateral view only (®gure 4M). Leg 1 (®gure 4N) reduced to a seta and a tiny knob tipped with two setules and a small tubercle, or only two setules (®gure 4O). Etymology. The speci®c name papilla is Latin (= nipple, teat, bud), it refers to the reduction of the endopod on leg 2 to a bud-like structure. Remarks. The new species can be distinguished from its two congeners by the following three characters:

Characters	hoi	longitruncus	papilla
ratio of female trunk (length/width)	4.7 5 1	5.8 5 1	8.9 5 1
annular sculptures on male antenna	present	present	absent
terminal claw of male maxilliped	absent	absent	present
leg 2 in male	absent	absent	present

Since Yamaguti (1939) failed to describe the ®ne structures of B. longitruncus , it is impossible to point out if there are further diOEerences among these three species. However, more diOEerences from B. hoi are given after the redescription of that species.