Hypselodoris maridadilus is a species of colourful sea slug or dorid nudibranch, a marine gastropod mollusk in the family Chromodorididae.

[2] This nudibranch is found in the Western Indian Ocean, from South Africa to the Red Sea.

[3] Hypselodoris maridadilus has a white to cream or yellow body with five purple longitudinal lines, and a purple bordered mantle.

It is similar in appearance to Hypselodoris whitei which differs slightly in having white-tipped rhinophores and gills.

This species can reach a total length of at least 35 mm (1.4 in).