Cochinorchestia

Lowry, J. K. & Springthorpe, R. T., 2015, Coastal Talitridae (Amphipoda: Talitroidea) from north-western Australia to Darwin with a revision of the genus Cochinorchestia Lowry & Peart, 2010, Zootaxa 3985 (2), pp. 151-202 : 177-178

Cochinorchestia sp.

( Fig. 16 )

Microrchestia sp. Bussarawich, 1985: 11, fig. 8.

Material. 100 specimens both males and females collected from decomposed mangrove leaves, Klong Pak, Panang; 10 specimens collected from Klong Bang Sai; 8 specimens collected from Ao Yon; 10 specimens collected from Ao Nam Bor and twenty specimens collected from rotten wood from Ko Yao Yai. The specimens could not be found among the collections of the Phuket Marine Biodiversity Center ( PMBC) and are presumed lost (Dr Charatsee Aungtonya pers comm).

Habitat. Supralittoral, mangroves, under decomposed mangrove leaves and rotten wood.

Description. Based on male, 10 mm ( Bussarawich 1985: 11, fig. 8).

Head slender scales on ventroproximal surface unknown. Eye large (greater than 1/3 head length). Antenna 1 reaching slightly beyond end of antenna 2 peduncle. Antenna 2 slender, article 5 longer than article 4, flagellar articles final article unknown. Maxilla 1 with small palp, 2-articulate. Maxilliped palp article 2 distomedial lobe well developed; article 4 small, well defined.

Pereon. Gnathopod 2 sexually dimorphic; subchelate; basis slightly expanded; ischium without lobe on anterior margin, with distally rounded anterodistal lobe on medial surface; posterior margin of merus, carpus and propodus each without lobe covered in palmate setae; carpus triangular, reduced (enclosed by merus and propodus), posterior lobe absent, not projecting between merus and propodus; propodus subovate, 1.6 × as long as wide; palm extremely acute, reaching about 44% along posterior margin, smooth, without protuberance or shelf near dactylar hinge, lined with about 3 lateral robust setae, cuticular patch at corner of palm unknown; dactylus subequal in length to palm, sinusoidal, without anteroproximal bump, posterior margin smooth, not modified distally, blunt.

Pleon. Uropod 1 peduncle with 9 robust setae, distolateral robust seta present, large (1/4 length of outer ramus), with simple tip; inner ramus subequal in length to outer ramus, inner ramus with 3 marginal robust setae in 1 row; outer ramus with 3 marginal robust setae. Uropod 3 peduncle with 1 robust seta; ramus not fused to peduncle, shorter than peduncle, as long as broad, triangular, with 2 apical setae. Telson as broad as long, entire, dorsal midline vestigial or absent, with 2 apical robust setae per lobe.

Remarks. Based on figure 8 ( Bussarawich 1985) these specimens appear to be an undescribed species of Cochinorchestia . The male gnathopods are similar to the gnathopods of C. morini from Parangipettai in southeastern India.

Distribution. Thailand. Klong Pak, Panang; Klong Bang Sai; Ao Yon; Ao Nam Bor Ko Yao Yai ( Bussarawich 1985)

Figures

FIGURE 16. Cochinorchestia sp., male, 10 mm, Klong Pak Panang (After Bussarawich, 1985: 11, fig. 8)