Shell of the Week: The Atlantic Gray Cowrie

The Atlantic Gray Cowrie (Luria cinerea) is a relatively common species of Cowrie inhabiting shallow coral reef areas in the tropical western Atlantic. The species is not found, however, on the coast of Southwest Florida. As happens with most species from the cowrie family (Cypraeidae), the Atlantic Gray Cowrie bears planktonic larvae. Their offspring drift in the sea until metamorphosis to their adult, bottom-crawling lives.

Luria cinerea, from off Pompano Beach, Florida. Illustration by James F. Kelly.

The larval shell is very distinctive from the adult one in this and other species of Cowries. The images show three growth stages in the life of the Atlantic Gray Cowrie. They are all so different, yet all represent stages in the development of the same species.

The Atlantic Gray Cowrie. Scanning electron micrographs, from left: two views of the planktonic larval shell; juvenile shell after settlement to adult life (1 mm = 0.04 inch).

*Do not confuse the Atlantic Gray Cowrie with the invasive Thrush Cowrie (Naria turdus).