Colpodaspis pusilla is a tiny sea slug with an internal shell. The shell is completely enclosed by a thin mantle. The skin contains secretory glands which produce a milky secretion when the animal is disturbed. The foot produces a sticky secretion. The posterior foot is very short.This Headshield slug is white with white pigments.
Certainly feeding on sea squirts, including Clavelina lepadiformis and Pycnoclavella stolonialis.