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 64 m (210 ft), though rarely deeper than 25 m (82 ft) or shallower than 2 m (6.6 ft).

It can also be found in the aquarium trade.

[1] This species can reach 15 cm (5.9 in) in total length.

[2] It feeds on small organisms such as crustaceans, plankton and fish eggs, and the young are cleaner fish.