Rochinia cidaris n. sp.

(Figs. 7 A–C, 9A–D)

Material examined. Holotype: male (19.0 × 11.5 mm) (MNHN-IU-2014-19044), stn CP4448, New Ireland, Papua New Guinea, 02°13’S 150°12’E, 564–743 m, coll. KAVIENG 2014, 1 September 2014.

Diagnosis. Carapace pyriform, covered with short, thin setae, smooth when denuded. Supraorbital eave with pre-orbital spine strong, directed upwards. Postorbital lobe cup-like. Carapace with 9 spines; 2 hepatic spines directed outwards, swollen basally; 1 mesogastric spine; 2 epibranchial granules; cardiac region slightly swollen with 1 cardiac spine; 2 short metabranchial spines; 2 long lateral branchial spines, directed outwards; 1 short posterior spine medially (Fig. 7A). Antennal flagellum shorter than pseudorostral spines. Basal antennal article longer than broad, distal angle of article blunt. Buccal frame covered by third maxilliped. Pterygostomial region with 4 granules on outer margin (Fig. 7B). Male chelipeds slender; propodus slightly inflated, with outer margin carinate; carpus outer surface with single carinate margin; merus triangular in cross-section; single granule on inner proximal surface. Ambulatory legs slender; P2 longest. Male thoracic sternum with sternites 3 and 4 depressed; sternites 3 and 4 with margin constricted anteriorly, posterior widest. Male pleon with triangular telson and 6 somites free (Fig. 7B). G1 straight, slightly constricted on distal third, distal tip with slight rounded angle on upper edge near rounded tip (Fig. 9 A–D).

Etymology. The term “ cidaris ” is a Latin term for crown, alluding to the spiny anterior half of the carapace of the crab. The name is used as a noun.

Remarks. Rochinia cidaris n. sp. is morphologically similar to R. riversandersoni Alcock, 1895, from off the Malabar coast, India, but differs in having less distinct carapace spines and possessing strong pre-orbital spines (Fig. 7A, C) (versus more distinct carapace spines and weak pre-orbital spines; cf. Alcock & Anderson 1896: pl. 22 figs. 2, 4). Rochinia cidaris n. sp. has nine carapace spines (Fig. 7A) (versus 11 carapace spines on R. riversandersoni (cf. Alcock 1895: 203; Alcock & Anderson 1896: pl. 22 figs. 2, 4); and its basal anternnal article has a blunt distal angle (Fig. 7B) (versus basal antennal article with sharp distal angle in R. riversandersoni (cf. Alcock 1895: 203; Alcock & Anderson 1896: pl. 22 fig. 2a).

The new species is currently only known from its type locality, New Ireland, Papua New Guinea.