The plain black phyllidiid, with single pink tubercles rather than raised clusters.
A firm-bodied dorid to about 6 cm, black, with low pink to rose tubercles set singly or in short lines along the back rather than gathered onto raised mounds, and with black rhinophores. There is no gill plume; the phyllidiids breathe through folds under the mantle edge. The separations within the genus are all of this kind. Phyllidiella pustulosa, much the commonest of them, carries its tubercles in compact groups of three or more on distinctly raised humps, and P. rosans runs the pink into continuous longitudinal ridges rather than leaving it as separate tubercles.
These are differences that need a sharp photograph taken square from above, and an animal recorded only from an oblique angle is often better left at Phyllidiella sp. than forced onto a name. A good proportion of the phyllidiids in circulation in photo libraries are misfiled for exactly this reason.
Feeds on sponges and holds their chemistry in its skin, which accounts for its moving about in the open by day. Recorded from about 3 to 30 m on sponge-covered rubble and rock. Black subjects take light from the side rather than straight down the lens, or the tubercles disappear into the ground.
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.
