Cortez rainbow wrasse  The Cortez rainbow wrasse ("Thalassoma lucasanum") is a species of wrasse native to the eastern Pacific Ocean from Baja California to Peru, as well as around the Galapagos Islands. It is a reef inhabitant, occurring in small schools from the surface to depths of , though rarely deeper than or shallower than . It is generally very common. It can also be found in the aquarium trade. This species can reach in total length. It feeds on small organisms such as crustaceans, plankton and fish eggs, and the young are cleaner fish.