Chandraniscus eastwardae, George, 2004

George, Robert Y., 2004, Deep-sea asellote isopods (Crustacea, Eumalacostraca) of the north-west Atlantic: the family Haploniscidae, Journal of Natural History 38 (3), pp. 337-373 : 343-344

Chandraniscus eastwardae n. sp.

(figure 4)

Diagnosis. Chandraniscus with frontal margin of cephalon with a median projection. Posterolateral angles of pleotelson extending beyond the posterior median margin of pleotelson. Flagellum of antenna 1 with six articles and flagellum of antenna 2 with 11 articles.

Material examined. Holotype: male, length 2.6 mm, maximum width 1.0 mm. USNM Cat. No. 138674.

Type locality. R / V Eastward Sta. 7813, site Beta over the Carolina lower slope .

Etymology. The species is named after Duke University Research Vessel Eastward employed for this study, in the deep sea off the North Carolina coast.

Description of male. Body oval. Pleotelson shield-shaped, longer than the posterior four pereonites combined. Cephalon broader than long, lateral margin rounded. Rostral process triangular and blunt, projecting slightly beyond the posterolateral angles of the cephalon. First pereonite shorter than the cephalon and second pereonite combined. Pereonites 2–4 increasing in width, with posterior sutures between pereonites 2–7 distinct. Pereonites 5–7 subequal. Pleotelson shield-shaped, with posterolateral angles pronounced, projecting far beyond the rounded posterior mid-margin.

Antenna 1 reaching to the end of the peduncle of antenna 2, peduncular articles 1 and 2 subequal and article 3 short, less than one-third the length of article 2. Flagellum of five articles, terminal article the shortest and bearing long distal setae. Antenna 2 with robust peduncle with five articles and flagellum composed of 11 articles. Maxilliped with two coupling hooks, distal margin of endite carrying 12 small ornate spine-like setae. Maxilliped palp of five articles, basal article short and article 2 about twice as long as article 3. Pereopod 5 ambulatory and slender; basis one-third the length of ischium in pereopod 3 and merus less than half the length of carpus, propodus as long as carpus, dactylus short. Pleopod 1 in male with a triangular sympod, distal part with ‘pear-shaped’ plates bearing three setae on each. Male second pleopod with a coiled copulatory endopod. Uropod mostly concealed by the pleotelson, with only the tip visible dorsally. Uropod uniramous with single segment, distal tip of ramus with four setae, one very elongated.

Remarks. Chandraniscus eastwardae n. sp., in having similar shield-like pleotelson configuration, is somewhat similar to the four other new species described in this study. The first species, also from the same study site Beta on the lower continental slope, Chandraniscus kussakini n. sp., is possibly a sympatric species and is clearly distinguished from C. eastwardae in having a very pronounced mid-dorsal spine on the cepahalon, and in the uropod ramus extending to the tip of the posterolateral angles of pleotelson. The second species, Chandraniscus negoescuae n. sp. from site Sigma on the continental rise, is strikingly different from C. eastwardae in having a quadrangular cephalon, lacking any mid-dorsal cephalic projection.