Black with green ridges and a green gill plume, grazing sea squirts in the open.
A polycerid to about 10 cm, black to very dark brown, with a raised ridge along the midline of the back and a series of lower ridges and blotches in a strong translucent green. The rhinophores and the gill plume are the same green. The crest is what the name refers to, though on a moving animal it is the green gills that carry across a metre of water: Nembrotha kubaryana has orange on the gills, rhinophores and foot margin, N. lineolata dark red gills and fine pale lines, and N. chamberlaini orange spots ringed in green. Green on the gill plume, with no orange anywhere, is this one.
Feeds on colonial ascidians, taking them with an everted oral tube, and several animals are often on one colony at once. Like the rest of the genus it holds the prey’s defensive chemistry and makes no attempt at concealment, so it is found in the open on rock, rubble and wreckage rather than tucked away. Recorded from about 5 to 35 m.
At this size it is among the easier nudibranchs to photograph properly — large enough to fill a frame without extreme magnification, slow enough to allow a considered composition, and usually raised on a colony rather than flat on sand. White spiral egg ribbons are laid on or beside the food colony and are often the thing that leads to the animal.
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.
