Lucascinus keijibabai (Takeda & Miyake, 1971) Takeda & Miyake, 1971

Poore, Gary C. B., Guinot, Danièle, Komai, Tomoyuki & Naruse, Tohru, 2016, Reappraisal of species attributed to Halicarcinus White, 1846 (Crustacea: Decapoda: Brachyura: Hymenosomatidae) with diagnosis of four new genera and one new species from New Ireland, Papua New Guinea, Zootaxa 4093 (4), pp. 480-514 : 506

Lucascinus keijibabai (Takeda & Miyake, 1971) n. comb.

( Fig. 10 h)

Rhynchoplax keijibabai Takeda & Miyake, 1971b: 165 –168, figs 1, 2.

Halicarcinus keijibabai— Lucas 1980: 164. — Ng & Richer de Forges 1996: 265, fig. 2.

Material examined. Holotype. New Caledonia. Plum, 9 June 1968, coll. K. Baba, KMNH-ZLKU 13089 (1 male, 2.1 mm). Paratype. Collected with holotype, KMNH-ZLKU 13090 (1 ovigerous female, 1.9 mm).

Other material. New Caledonia. Thio, 1 m, MNHN IU-2014-7146 (B25970), (1 male). Ricaudy Reef, MNHN IU-2014-7135 (6 males, 7 females); ZRC 2006.0089 (2 males, 1 female). Ouemo Beach, Nouméa, intertidal, ZRC 1994.4283 (1 male).

Diagnosis. Carapace 1.1 times as long as wide in male, slightly narrower than long in female. Rostrum tapering, upturned, rod-like, 0.5 carapace length in male, 0.3 in female; apex without long setae. Supraocular eave arching, narrow, defined anteriorly by substantial anteriorly directed upturned pseudorostral tooth; postocular margin defined by anterior margin of subhepatic region, without tubercle, without notch separating it from supraocular eave. Subhepatic region with 2 small conical tubercles hardly visible in dorsal view; anterolateral margin unarmed, epibranchial tooth absent; branchiostegal region with 1 small spiniform tooth located at about midlength of carapace. Antennule not produced laterally; proepistome (interantennular septum) apparently absent. Male cheliped propodus 6 times as long as depth at base of fingers, upper margin convex along length of fixed finger; cutting edge of fixed finger with proximal conical tooth, deeply concave over middle half, straight distally; dactylus 0.3 length of propodus, cutting edge with conical proximal tooth, straight distally. Pereopodal dactyli with erect teeth along middle two-thirds to three-quarters of length. Male gonopod 1 with swollen base, distal part stout, tapering, about as long as greatest length of base, with subapical pectinate setae.

Distribution. New Caledonia, intertidal reef.

Remarks. Characters differentiating L. keijibabai from L. coralicola were fully discussed by Ng & Richer de Forges (1996) (as Halicarcinus ) who illustrated several important features. The male cheliped of these two species are more similar to each other than they are to L. bedfordi . L. keijibabai is unique within the new genus in the absence of a proepistome.

Figures

FIGURE 10. Lucascinus coralicola (Rathbun, 1909). Male, 4.7 mm, CBM-ZC 3632: a, carapace, dorsal view, b, frontal region, ventral view; c, thoracic sternum; d, left cheliped, upper view; e, chela, lateral view; f, gonopod 2, outer (ventral) view; g, same, inner (dorsal) view. Lucascinus keijibabai (Takeda & Miyake, 1971). Male, ZLKU 13089 (holotype, male, 2.1 mm: h, frontal region, ventral view. Scale bars a – e, h = 1 mm; f, g = 0.5 mm.