Body slender, oval; visceral mass visible through body wall. Body and wings dark. Posterior footlobe absent in some specimens, small when present. Median tubercle in animals with and without posterior footlobes. Buccal cones of same type as in genus Clione, but larger. Median radula plate with one long spine on free border, sometimes two reduced lateral ones. Jaw reduced. Hook sacs small, transparent, shallow, each with fewer than 15 short curved hooks. Row of rugosities between hook sacs represents jaw. Lateral gill absent, its site marked by transparent lacunar spot. Radula formula 2-1-2 to 6-1-6. Body length 10 mm.