Faithful Sea Slug

Goniobranchus fidelis is a species of colourful sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae.

Description

It can reach more than 25 mm length. The body of the animal can be described in two distinct parts: the foot and the mantle. The foot is stretched and almost covered by the edges of the wide mantle, it is cream in colour. The colour pattern of the mantle is marked by a creamy white area with scalloped edges. The whole wide margin of the mantle is orange to red, a burgundy like border, with a variable thickness from one animal to the other, delimiting the two coloured areas. The rhinophores are laminated, contractile and greyish color, whose intensity varies from one animal to another with lighter colour at the tip. Gills have the same colour as the rhinophores but they are retractable.

Distribution & Habitat

Distribution of Goniobranchus fidelis include tropical Indo-West Pacific and Red Sea. Its habitat is the external reef area as well on the top or on the slope up to 20 m deep with a preference for dead corals.

Biology

This sea slug is benthic and diurnal, moves without any fear of being taken for a prey, because of the presence of defensive glands distributed in its body tissues and shown to the potential predators through its warning coloration.