Achaeus lacertosus Stimpson, 1858

(Fig. 5B)

Material examined. RV Hakuhō Maru KH-72-1 cruise, sta. 29, 1 ovig. ♀ (CB 3.2×CL 3.8 mm), NSMT-Cr 30707; 1 ovig. ♀ (3.2× 4.1 mm), NSMT-Cr 30708.

Remarks. This short-neck species, Achaeus lacertosus (Fig. 5B), has two synonyms, namely A. breviceps Haswell, 1880 (fide Haswell, 1882) and A. spinifrons Sakai, 1938 (fide Griffin and Yaldwyn, 1966), with figures by Stimpson (1907), Stephensen (1945), Griffin (1970) and Sakai (1938, as A. spinifrons; 1976). As briefly diagnosed by Griffin and Tranter (1986), A. lacertosus is characteristic in having the rostral anterior margin fringed with spinules, the smooth carapace surface with convex gastric, cardiac and branchial regions, the hepatic outer margin being strongly expanded, with an obtuse tip, and the strongly curved dactylus of the last ambulatory leg.

Distribution. According to Griffin and Tranter (1986), this species is widely distributed in the Indo-West Pacific from Japan to South Africa through intervening localities in the West Pacific, Australian waters and the Indian Ocean including the Persian Gulf. The bathymetric range is from 5 to 90 m, but Griffin and Tranter (1986) recorded two specimens from Singapore collected during low tide.