|The family Polyceridae
includes both nocturnal and diurnal species that often have elaborate
tubercles or dorsal processes. They are specialized predators that eat
bryozoans, tunicates, brittle stars or other nudibranchs. Some species
in the genus Plocamopherus
can swim by flexing
their bodies latterly and are bioluminescent. There are at least 18
species known from Hawaii in eight genera (Crimora, Kalinga, Kaloplocamus, Plocamopherus, Polycera, Roboastra, Tambja and Thecacera).