Home > Invertebrates > Mollusks > Gastropods > Helmets > Casmaria ponderosa

Created 10/16/2025

Family Cassidae

INDO-PACIFIC / HAWAII

Casmaria ponderosa



Oahu.  @ Dan Polhemus

  
   

PONDEROUS HELMET

Uncommon in sand deeper than 30 feet, and dead shells are common in beach drift or hermit-crabbed.  Shoulder with obsolete cornations, outer lip & columella thick, five to twelve  dash-like denticles along outer lip, and numerous elongated teeth encircling the wine-colored aperture.  Attains 4 inches, 100 mm.  Red Sea to Japan, Hawaii, and the Society Islands.  Part of a species complex, formerly lumped together in Hawaii with Casmaria kayae.