Trapania is a genus of sea slugs, specifically dorid nudibranchs, marine gastropod molluscs in the family Goniodorididae.

[2] The genus Trapania is distinguished from other goniodorid nudibranchs by the possession of two pairs of lateral papillae which arise from the remnant of the pallial margin and curve backwards parallel with the main body axis.

One pair arises just outside the rhinophores and the other just outside the gill cluster.

A pair of prominent oral tentacles are attached to the front of the head.

Species within the genus Trapania include:[2]