Trapania naeva is a species of sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Goniodorididae.
This species was described from Ryukyu, Japan. It is widespread in the Indo-Pacific region with records from the African coast (Tanzania, Kenya) through the Maldives, Indonesia and Western Australia to Fiji.
This goniodorid nudibranch is translucent white, with a pattern of large dark brown or black spots with smooth edges on the body. The gills, papillae, oral tentacles and rhinophores are dark brown or black.
Trapania naeva probably feeds on Entoprocta which often grow on sponges and other living substrata.