Trapania squama is a species of sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Goniodorididae.

This species was described from Madang, Papua New Guinea.

[2] The body of this goniodorid nudibranch has a pattern of white patches with thin lines of dark brown between them, giving a scaled appearance.

The network of brown lines forms small square or diamond shapes where the lines intersect.

[2] The animals from the Marshall Islands apparently feed on a species of bryozoan.