Eastern Pacific: Gulf of California to Peru, including the Galapagos Islands.
Lives in empty tube-worm snail shells, often extending the head from the opening. Feeds by joining loose groups of look-alike rainbow wrasse and darting out to nip at nearby fish, taking mucus and perhaps small bits of flesh.
The skin of larger fishes is the mainstay of the diet, although they are also known to eat eggs. Oviparous.
Eggs are demersal and adhesive. Eggs are attached to the walls of the parent's shelter and are brooded by the male parent