A hard flat dorid with the texture of coarse sandpaper, usually under loose rubble by day.
A large flat dorid, oval in outline and to about 8 cm, with a mantle that is stiff and almost rigid rather than soft, and a surface finely granular to the point of feeling like coarse sandpaper. The margin is wide and thin and lies flat against the substrate, so an animal pressed to the underside of a rock has almost no relief and is easily passed over. Colour is usually a flat red-brown, brick or cream, sometimes with darker blotches.
The gill plume and the rhinophores retract into pockets that close flush with the mantle, leaving two small holes and a slightly raised circle, and a disturbed animal will sit like that for a long time. The underside is often as useful for identification as the top, since several species carry dark markings on the foot and on the mantle margin that the upper surface does not show.
The genus feeds on sponges. Animals are under loose rubble and rock during the day and out on the open surface at night, which is when most are recorded. Species are separated on the underside pattern, the granulation and the colour of the gill, and a record from a photograph of the back alone usually stays at the genus. Recorded from about 2 to 25 m.
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.
