Ethusina pubescens Chen, 1993

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 : 569-570

Ethusina pubescens Chen, 1993

( Fig. 24 )

Ethusina pubescens Chen, 1993: 336 (key), 341, fig. 19; 1997: 624. — Ng & Ho 2003: 72 (list).

TYPE MATERIAL. — Holotype: cl 9.6 mm, cw 9.6 mm, MUSORSTOM 5, stn CP 323 ( MNHN- B 19060); paratypes: cl 9.6 mm, cw 9.5 mm, MUSORSTOM 5, stn CP 323 ( MNHN-B 22256 );

cl 9.7 mm, cw 9.6 mm, MUSORSTOM 5, stn CP 324 ( MNHN-B 19061 ) ;, same station ( IOAS). TYPE LOCALITY. — Chesterfield Islands , 21°18.52’S, 157°57.62’E, 970 m.

MATERIAL EXAMINED. — Chesterfield Islands. MUSORSTOM 5, stn CP 323, 21°18. 52’S, 157°57.62’E, 970 m, 14.X.1986, 1 holotype ( MNHN-B 19060), 1 paratype ( MNHN-B 22256). — Stn CP 324, 21°15.01’S, 157°51.33’E, 970 m, 14.X.1986, 1 paratype ( MNHN-B 19061). New Caledonia. BATHUS 3, stn CP 842, 23°05’S, 166°48’E, 830 m, 1.XII.1993, 1 ( MNHN-B 22878), 1, 1 ( MNHN-B 28660). — Stn CP 844, 23°06’S, 166°46’E, 908 m, 1.XII.1993, 2, 1 parasitized by Sacculina sp. ( MNHN-B 28661).

Wallis and Futuna Islands. MUSORSTOM 7, stn DW 565, 11°47.4’S, 178°25.3’W, 900 m, 20.V.1992, 1 ( MNHN-B 22879).

DISTRIBUTION. — Known from the Chesterfield Is ( Chen 1993), New Caledonia ( Chen 1997), and Wallis and Futuna Is ( Chen 1997). Depth: 830-970 m ( Fig. 34 ).

SIZE. — Maximum size: cl 9.7 mm, cw 9.6 mm ( MNHN-B 19061), cl 10.8 mm, cw 10.9 mm ( MNHN-B 28660).

REMARKS

Ethusina pubescens was named after the very short, very sparse pubescence on the dorsal surface of the carapace and abdomen, which unfortunately was emphasized in the illustration of the holotype ( Chen 1993: fig. 19a). More characteristic is the very slender, acute outer orbital teeth that nevertheless do not reach the frontal teeth. The P2 and P3 are long and slender. The branchial regions are conspicuously more expanded laterally than the anterior portion of the carapace, giving the carapace of both sexes a pear-shaped appearance.

The G1 were unfortunately drawn incorrectly. They were shown to have a slight extension close to the tip, thus making them look like a foot ( Chen 1993: fig. 19d). One of the two first pleopods of the holotype ( MNHN-B 19060), the one that was drawn by Chen, is no longer extant but the second shows a slimmer, symmetrical tip ( Fig. 24 ).

Figures

FIG. 24.— Ethusina pubescens Chen, 1993, holotype cl 9.6 mm, cw 9.6 mm, Chesterfield Islands,Coriolis Bank, MUSORSTOM 5, stn CP 323, 970 m (MNHN-B 19060), left G1, ventral view. Scale bar: 1 mm.

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