Petrolisthes perdecorus Haig, 1981

Osawa, Masayuki, 2007, Porcellanidae (Crustacea: Decapoda: Anomura) from New Caledonia and the Loyalty Islands, Zootaxa 1548, pp. 1-49 : 27-28

Petrolisthes perdecorus Haig, 1981

( Fig. 8 E)

Petrolisthes perdecorus Haig, 1981a: 265 , fig. 1 (type locality: Howland Island).

Material examined. Loyaly Islands. Atelier LIFOU. Santal Bay. St. 1410 (St. 63A), between Cap Wekutr and Cap Wajez, 20°56.7’S, 167°03.1’E, 2–4 m, 25 Nov. 2000, 2 males CL 4.3, 4.8 mm, 1 ovig. female CL 4.2 mm. St. 1456 (St. 66), Cila, 20°49.3’S, 167°10.4’E, 25–30 m, 26 Nov. 2000, 1 male CL 4.0 mm.

Remarks. Petrolisthes perdecorus is distinguished from the other Indo-West Pacific species of the genus by having the carapace with protogastric lobes each bearing a spine at the lateral extremity, distinctly trilobate rostrum armed with marginal spines ( Fig. 8 E), and carpi of the chelipeds with scattered small spines on the dorsal surface.

Distribution. Petrolisthes perdecorus was recorded only from Howland Island, located just north of the equator in the central Pacific ( Haig 1981a). This is the second record of the species, collected from depths of 2–30 m in the Loyalty Islands.

Figures

FIGURE 8. Petrolisthes militaris (Heller, 1862), male, CL 10.0 mm, New Caledonia, Maitre Islet (A, B); Petrolisthes scabriculus (Dana, 1852), male, CL 7.6 mm, New Caledonia, Maitre Islet (C, D); Petrolisthes perdecorus Haig, 1981, male, CL 4.8 mm, Loyalty Islands, St. 1410 (E). A, C, rostrum and right ocular peduncle, dorsal view; B, D, left cheliped (marginal setae drawn as simplified, short plumose setae on transverse ridges omitted); E, rostrum and ocular and antennal peduncles, dorsal view. Scales equal 1.0 mm.