Omobranchus obliquus (Garman, 1903)
(ROUNDHEAD BLENNY)
In Hawai`i, this blenny--easily identified by its oblique markings--is known only from O`ahu, where it was likely introduced, perhaps in the 1950s. It occurs only in the most protected locations and is easily seen at Coconut Island (Moku o Lo`e) in Käne`ohe Bay, where it lives on piers, pilings, buoys, and mangrove roots. The female pictured was photographed on a root partly covered with bright orange colonial tunicates. Males, slightly larger than females, have a yellow chin and yellow pelvic fins. Some authors identify it as a subspecies of the similar Australian Roundhead Blenny, O. rotundiceps. Several other blennies have been introduced to O`ahu. One, the Tasselled Blenny Parablennius thysanius, has occurred in the vicinity of the Käne`ohe Bay Yacht Club since the 1970s. To almost 2 in. Eastern Indian Ocean, Western and Central Pacific. Photo: Coconut Island (Moku o Lo`e) Käne`ohe Bay, O`ahu, 2 ft.