Horned Helmet Shell, Cassis cornuta

This large species lives on sand in shallow water in the Red Sea and throughout the Indian and western Pacific Oceans. It grows in regular increments, with each new section a larger version of the previous one; the large horns do not fully develop until the final stage. Adults can live for many years, their shells gradually eroding and acting as a home to sponges, corals, boring bivalves and other marine organisms.