The phyllidiid separated from the common pustulose one by yellow-tipped tubercles.
A firm-bodied dorid to about 6 cm, the body hard and rubbery rather than soft, grey to blue-grey over a black ground, and carrying conical tubercles that are pink to rose at the base and tipped with yellow. The rhinophores are yellow. The tubercles stand as separate cones and do not fuse into ridges. Against Phyllidiella pustulosa, which shares the shape and is far commoner: pustulosa’s tubercles are pink-grey with no yellow tip, are gathered into clusters, and its rhinophores are black. Against Phyllidia varicosa: varicosa’s tubercles run together into long blue-grey ridges tipped in yellow, with a black line down the midline. Like the whole family it has no gill plume, breathing through folds beneath the mantle margin.
Feeds on sponges and secretes the terpenes it takes from them through the skin, which is why an animal this conspicuous grazes in the open in daylight. The compounds are potent enough that a phyllidiid confined in a bucket or a bag with fish has killed them, which is a documented result rather than a diving story, and a reason not to collect one.
Recorded from about 3 to 30 m on sponge-covered rubble and rock. The yellow tubercle tips are small and the body is dark, so an exposure set for the black ground tends to lose them; the tips are the part of the animal an identification turns on.
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.
