Petrolisthes elongatus (H. Milne Edwards, 1837 )

Osawa, Masayuki, 2007, Porcellanidae (Crustacea: Decapoda: Anomura) from New Caledonia and the Loyalty Islands, Zootaxa 1548, pp. 1-49 : 22

Petrolisthes elongatus (H. Milne Edwards, 1837)

Porcellana elongata H. Milne Edwards, 1837: 251 (type locality: New Zealand). Petrolisthes elongatus .— Miyake, 1943: 77, text-figs. 14, 15.

Material examined. New Caledonia. Platier de Thio, St. Gabriel, lagoon, low tide, 0.8 m, 19 May 1996, coll. B. Richer de Forges, 1 male CL 3.3 mm.

Remarks. The small specimen from New Caledonia agrees well with the material on hand of P. elongatus collected from Kaikoura, New Zealand. Petrolisthes elongatus is allied to P. japonicus (de Haan, 1849), but is distinguished by the median lobe of the rostrum being more strongly produced forward, median lobe of the third thoracic sternite being comparatively higher, third segment of the antennal peduncle with a small spine on the median anterior margin, dactyl of the larger cheliped with a rounded tooth on the median cutting region, and comparatively stouter ambulatory legs with dactyli each armed with four corneous spines (three spines in P. japonicus ).

Distribution. New Zealand, Tasmania, and some indefinite records from “coast of Australia ”; occurring intertidally and in shallow water down to 5–20 m ( Haig 1964). This is the first record of the species from outside of New Zealand and Australia.