Home > Invertebrates > Shells > Rissoidae > Zebina tridentata

Created 2/23/2026

Family Zebinidae

INDO-PACIFIC / HAWAII

Zebina tridentata

 Ma'ili tidepool, Oahu, 7 mm

 

THREE-TOOTHED RISSO

Common in sand under stones or rubble at any depth.  Solid, spire may be reflexed, with microscopic axial striae, often three denticles on the lower outer lip.  Denticle development is dependent on maturity of the outer lip.  Attains 0.5 inch, 12 mm.  Red Sea to Japan, Hawaii, and Rapa Nui.