Petrolisthes heterochrous Kropp, 1986

Petrolisthes heterochrous Kropp, 1986: 458, fig. 3 (type locality: Guam).

Petrolisthes militaris .— Yang, 1983: 1, pl. 1.— Yang & Xu, 1994: 113, fig. 1A. [Not Petrolisthes militaris (Heller, 1862)]. Petrolisthes [undescribed sp. 1, R. K. Kropp, MS].— Garth et al. 1987: 241, 253.

Material examined. New Caledonia. Récif Mbere, lagoon, 22°19.9’S, 166°13.2’E, Pente externe, 10–15 m, 7 Jan. 1993, coll. P. Bouchet, 2 ovig. females CL 4.2, 4.4 mm. Récif Mbere, lagoon, 22°19.9’S, 166°13.2’E, outer slope of reef, 25–30 m, 7 Jan. 1993, coll. P. Bouchet, 1 female CL 2.7 mm.

Loyalty Islands. Lifou Island. Santal Bay. Atelier LIFOU. St. 1418 (St. 16), Esao, 120°46.9’S, 167°07.9’E, 1–5 m, 21 Nov. 2000, 1 male CL 3.5 mm. St. 1435 (St. 18), Lefèvre (= Nem), 20°55.2’S, 167°0.7’E, 5–30 m, 8 Nov. 2000, 3 males CL 2.8–3.7 mm, 2 ovig. females CL 3.7, 4.2 mm. St. 1435 (St. 18), Lefèvre (= Nem), 20°55.2’S, 167°00.7’E, 5–30 m, 8 Nov. 2000, 4 males CL 1.9–2.7 mm, 1 female CL 2.6 mm. St. 1421 (St. 28), Huca Hutighé Island, 20°52.4’S, 167°08.5’E, 4 m, 26 Nov. 2000, 1 male CL 4.7 mm. St. 1421 (St. 28), Huca Hutighé Island, 20°52.4’S, 167°08.5’E, 4 m, 26 Nov. 2000, 1 female CL 2.6 mm. St. 1421 (St. 28), Huca Hutighé Island, 20°52.4’S, 167°08.5’E, 4 m, 26–27 Nov. 2000, 3 males CL 3.5–4.3 mm, 1 female CL 2.5 mm, 4 ovig. females CL 3.6–4.3 mm. St. 1457 (St. 67), Ngoni, 20°46.8’S, 167°02.75’E, 5–10 m, 27 Nov. 2000, 1 male CL 2.6 mm. St. 1434 (St. 12), Huca Htighé Island, 20°52.5’S, 167°08.1’E, 5–20 m, 6 Nov. 2000, 1 male CL 2.5 mm, 1 ovig. female CL 3.2 mm. St. 1410 (St. 63A), between Cap Wekutr and Cap Wajez, 20°56.7’S, 167°03.1’E, 2–4 m, 25 Nov. 2000, 1 male CL 3.5 mm. St. 1410 (St. 63B), between Cap Wekutr and Cap Wajez, 20°56.7’S, 167°03.1’E, 2-4 m, 25 Nov. 2000, 1 ovig. female CL 2.5 mm.

Remarks. The distinctly trilobate rostrum immediately distinguishes P. h e t e ro c h ro u s from two congeners, P. militaris and P. scabriculus .

Yang (1983) and Yang & Xu (1994) recorded P. militaris from the Xisha and Nansha Islands, China. However, the illustrated specimens seem referable to P. heterochrous on the basis of the characteristic shape of the rostrum. Garth et al. (1987) recorded P. heterochrous as an undescribed species from Enewetak Atoll, Marshall Islands.

Distribution. Nansha and Xisha Islands in China, Ryukyu Islands, Mariana Islands, Marshall Islands, Chesterfield Islands; subtidal to 23 m; occurring in crevices in dead coral rubble, dead branching coral, and on the base of living coral (Yang 1983; Kropp 1984; Haig 1987; Yang & Xu 1994; Osawa 1998c). The specimens examined from New Caledonia and the Loyalty Islands were collected at the depths of 1– 30 m.