Body largely transparent, visceral mass visible through body wall. Shape variable, from droplet-shaped with extremely large head to barrel-shaped with head section about as large as body section. Wings implanted laterally in middle of body. Posterior and lateral footlobes separate. Median foot tubercle present. Radula formula: 3-1-1-1-3, with 8 rows. Median plate very fragile, thin, transparent; borders drawn out on each side. Dentition usually absent, sometimes very faint. Intermediate plates with a short top cusp and sometimes 2 to 4 small cusps near top. Body length 8 mm.