A new species of scorpion fish has been described from the Cocos Islands near Costa Rica in the eastern Pacific Ocean.
The new fish, which was named Scorpaena cocosensis, has just been described in the journal Copeia by Hiroyuki Motomura of the Australian Museum in Sydney.
Described from just a single specimen, the new species is said to be quite similar in appearance to Scorpaena russula and Scorpaena sonorae, both of which are also found in the eastern Pacific Ocean.
Motomura says that S. cocosensis can be distinguished from these two species on the basis of a number of characters:
"Eight dorsal-fin soft rays; well-exposed scales covering anteroventral body surface; interorbital ridges well developed, beginning just behind nasal spines, diverging anteriorly and posteriorly in dorsal view; lateral margins of frontal diverging posteriorly in dorsal view; upper posttemporal spine directed upward; posterior margin of maxilla just reaching level with posterior margin of pupil; posterior tip of pectoral fin reaching level with origin of third dorsal-fin soft ray; large head length (48.8% SL); large orbit diameter (16.9% SL); wide interorbital space between supraocular spine bases (9.2% SL)."
For details on how to distinguish the fish from other Scorpaeniformes see the paper: Hiroyuki Motomura (2004) - New Species of Scorpionfish, Scorpaena cocosensis (Scorpaeniformes: Scorpaenidae) from the Cocos Islands, Costa Rica, Eastern Pacific Ocean. Copeia: Vol. 2004, No. 4, pp. 818-824.