Bactrochondria papilla, Ho, Kim I.H. & Kumar, 2000

Ju-Shey, 2000, Chondracanthid copepods parasitic on flatfishes of Kerala, India, Journal of Natural History 34 (5), pp. 709-735 : 714-717

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.

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:

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.