Millimetre slugs with knobbed cerata, found by searching the hydroid they feed on.
Small dendronotids, most of them between four and twelve millimetres, with a smooth back carrying two rows of stout cerata, each ceras swollen and ringed with rounded tubercles so that it reads as a cluster of beads rather than a smooth finger. The rhinophores stand in tall funnel-shaped sheaths. That combination places the genus, and nothing else at this size on a hydroid stem looks like it.
Species are separated on colour, on the number and arrangement of the tubercles and on the identity of the hydroid, and a good many of the animals photographed on these coasts have no published name. Ground colour runs from translucent white and cream through pink to brown, usually with darker pigment spots on the cerata.
They live and feed on hydroids, taking the polyps, and are found by working over a hydroid colony rather than by searching open ground. The spawn is a short coiled white ribbon laid on the stem beside the animal, and it is often the spawn that is spotted first. A colony that holds one usually holds several. Recorded from about 3 to 25 m on rubble, rock and jetty structure.
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.
