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

[1] In the 10 mm animal, the back is dark blue, which turns violet towards the edge of the mantle which has an orange margin.

A broad midline runs along the back from the rhinophores to the gill, which it surrounds forming a circle, wider ahead.

Sides of foot blue, with a white line that goes from behind the genital opening to the beginning of the tail, but without continuing through it.

[1] The 18 mm animal has two yellow lines on the back which go from the gill to the head, passing between the rhinophores and joining in an arc in front of them.