The Grey brotula or Orange cusk eel, Bidenichthys consobrinus, is a cusk eel of the genus Bidenichthys, found around northern New Zealand from shallow depths to about 82.02 ft (25 m), in rock pools and reef areas of broken rock. Their length is between 1.57 and 2.36 in (4 and 6 cm).
The Grey brotula is a small cod-like fish, very similar to the Fleshfish, with long dorsal and anal fins and a small separate tail fin. Large pectoral fins contrast with very long single-ray pelvic fins set well forward under the gill openings. The eyes lie towards the top of the head and the mouth is large and bears prominent teeth. It has an eel-like swimming action.
There are two color forms – either a uniform orange-red, or a pale yellow.
The grey brotula is very secretive, living deep within crevices or caves, or under rocks, and is very seldom seen although it is locally very common.
Illustration by Dr Tony Ayling