Ethusa philippinensis Sakai, 1983

Castro, Peter, 2005, Crabs of the subfamily Ethusinae Guinot, 1977 (Crustacea, Decapoda, Brachyura, Dorippidae) of the Indo-West Pacific region, Zoosystema 27 (3), pp. 499-600 : 541

Ethusa philippinensis Sakai, 1983

Ethusa philippinensis Sakai, 1983b: 623 , fig. 1a, b.

TYPE MATERIAL. — Holotype:, poor condition, cl 11.3 mm, cw 9.5 mm ( Sakai 1983b), damaged, Albatross, stn 5453 ( USNM 195051 ).

TYPE LOCALITY. — Philippine Islands, Luzon, San Bernardino Strait, 13°12’N, 123°49’E, 72 m.

MATERIAL EXAMINED. — Philippine Islands. Albatross, stn 5453, Luzon, San Bernardino Strait, 13°12’N, 123°49’E, 72 m, 7.VI.1909, 1 holotype ( USNM 195051).

DISTRIBUTION. — Known only from the Philippine Is. Depth: 72 m ( Fig. 34 ).

SIZE. — Maximum size: cl 11.3 mm, cw 9.5 mm ( Sakai 1983b), unknown.

REMARKS

Ethusa philippinensis is known from only one specimen, the male holotype (USNM 195051). This specimen is soft and in a very poor condition. The left half of the anterior border of the carapace is still intact, however, so some important diagnostic characters are still discernible. The outer orbital teeth are very short, triangular, pointed, and are directed anteriorly, while the frontal teeth are also triangular but not as large and pointed as indicated by Sakai (1983b: fig. 1a). The median frontal sinus is actually deeper and wider than the orbital sinus. Sakai’s illustration also shows that the lateral borders of the carapace are straight, even if the branchial regions are slightly inflated. The G1 ( Sakai 1983b: fig. 1b) are also diagnostic to this species, having a foot-like shape but much different than that of E. parapygmaea Chen, 1993 ( Chen 1993: fig. 12e). Not indicated in the description is that the slender chelipeds are provided with many triangular, pointed teeth and that the anterior bor- der of the endostome reaches the antennular fossae of the basal antennular articles.

Figures

FIG. 34. — Bathymetric distribution of Indo-West Pacific ethusine crabs.