This marine slug is 80 to 100 mm in length, with southern specimens somewhat larger. Its colour is a mottled pale grey, densely patterned with short, brown broken lines. The wedge-shaped head has two sensory tentacles or
rhinophores. The
mantle is smooth in texture, but covered with folds and puckers, and the foot extends well beyond it. There is no remnant of a shell, and the feathery gill is tucked under the right side of the mantle. ==Ecology==