Phallocottus obtusus

The spineless sculpin was classified in its own monotypic genus because it differs from related genera by having a combination of no teeth on the palatine and having an arched lateral line with smooth skin, a short, rounded blunt preopercular spine and the gill membranes are broadly joined across the throat. The position of the anus, closer to the pelvic fins than the anal fin, is also a distinguishing character.

The spineless sculpin is found in the North Pacific Ocean where it is only known from the waters around the Aleutian Islands. It is a demersal fish that occurs at depths of from 0 to 150 m (0 to 492 ft).

== References ==

The spineless sculpin's genus name prefixes the name of the type genus of the Cottidae, Cottus with phallos, which means "penis". This is an allusion to the conical papillae at the anus. The specific name obtusus means "blunt" and is a reference to rather blunt and rounded spine on the preoperculum.