A red dorid the size of a fingernail, sitting on the red sponge it eats.
Small dorids, most of them between eight and twenty millimetres, oval and low, and coloured a flat red, orange-red or brick over the whole animal including the gill and the rhinophores. The upper surface is covered in caryophyllidia, short papillae stiffened with spicules and ringed with more of them, so the texture at magnification is matte and granular rather than smooth. The same kind of papillae, at a larger scale and in white, are what give the sea bunny Jorunna parva its fur. The gill is a small plume of a few branches at the back and retracts into a pocket.
The colour is not decoration. These animals feed on red and orange encrusting sponges, they sit on the sponge, and the match is close enough that an animal in plain sight is routinely passed over. The spawn helps: a flat coil laid on the sponge surface in much the same red or orange, slightly raised and more regular in outline than the sponge around it, and often the thing that is seen first. A colony with one slug on it commonly has two or three.
The genus is well represented in the region and poorly resolved. Species are separated on the radula, on the arrangement of the spicules and on the identity of the host sponge, none of which a photograph supplies, so records normally stay at the genus. Recorded from about 3 to 25 m on rubble, rock and jetty structure, wherever the encrusting red sponges are.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
