Rhopalophthalmus orientalis O.S. Tattersall, 1957

= Rhopalophthalmus egregius –W.M. Tattersall, 1921: p. 408 (in part)

Type locality. Coast of Ariak Sea, Japan, several fathoms (O.S. Tattersall 1957) .

Record from Thailand. Sapum Bay, Phuket Island (Hanamura et al. 2011).

Habitat and depth range. Estuarine to shallow coastal waters (Hanamura et al. 2011).

Distribution. This species is distributed from Japan (Nakazawa 1910; O.S. Tattersall 1957; Ii 1964; Hanamura et al. 2011), East China Sea (Liu & Wang 2000), Malacca (Tattersall 1965), Malaysia, Thailand and Indonesia (Hanamura et al. 2011).

Remarks. Among the species of the genus Rhopalophthalmus, this species can be easily distinguished by the rostrum being obtusely rounded; rudimentary endopods of eighth thoracopods in both sexes moderately developed, extending well beyond mid-length of basal plate of exopod (Hanamura et al. 2011).