Cavolinia inflexa (Lesueur, 1813) forma labiata (d'Orbigny, 1836)
Shell broader than in other forms (width 80% of length). Dorsal side flat, ventral side somewhat convex. Section behind lateral spines is smaller than in other forms (about 36% of the total shell length; vs 50% in C. inflexa forma inflexa, and 40% in C. inflexa forma imitans). Sculpture of faint growth lines. Lateral spines well-developed and distinctly bent caudally. Caudal spine long. Upper lip continuous with dorsal side of shell, rather long, distinctly tapering into sharp tip. Shell length: 8 mm, width: 5.5 mm .