Ethusa hirsuta McArdle, 1900

Material examined. RV Hakuhō Maru KH-72-1 cruise, sta. 30, 1 Ə (CB 10.2×CL

9.4 mm), NSMT-Cr 30700.

Remarks. The specimen examined is soft after ecdysis, with the carapace posterior part somewhat distorted, but identified as Ethusa hirsuta following the key by Castro (2005), who commented on the characters distinct from the close congeners and clarified synonymies: E. hirsuta recorded by Chen (1987) from Madagascar is really referable to E. machaera Castro, 2005; E. makasarica Chen, 1993 from the Makassar Strait is synonymous with E. hirsuta; and E. makasarica recorded by Chen (2000) from Vanuatu is in turn E. abbreviata Castro, 2005 . As a result, correct records of E. hirsuta are only those of McArdle (1900: 474), Alcock and McArdle (1902: pl. 59 fig. 12), Alcock and MacGilchrist (1905: pl. 72 fig. 1), MacGilchrist (1905: 257), Ihle (1916: 152), and Castro (2005: 524, fig. 11).

Ethusa hirsuta is characteristic in having the endostome extending beyond the posterior border of the antennular fossae, the straight, rather slender external orbital tooth, and the wide, shallow U-shaped orbital sinus.

Distribution. Gulf of Manaar, off Sri Lanka, Makassar Strait, Timor and Solomon Islands, and now from Australia, at depths of 112–1097 m, as plotted on the map by Castro (2005).