The Florida Cross-barred Venus, Chione elevata (Say, 1822), another member of the Venus clams family Veneridae, is one of the most common shells on the beaches of Southwest Florida. It measures up to about 25 mm (one inch). The shell valves have a characteristic sculpture of well-separated concentric ridges that are intercepted throughout the valve surface by more densely packed radial ribs. (The term radial in this case indicates a direction from shell from beak to edge, like the spokes on a wheel.) This resulting criss-crossed sculpture gives the species its common name. Do not mistake shells of this species for the Lady-in-waiting Venus, (Puberella intapurpurea), or the young of the Southern Quahog (Mercenaria campechiensis) and the Northern Quahog (Mercenaria mercenaria). Shells of these three latter species lack the radial ridges on their valve sculptures.
The Florida Cross-barred Venus, Chione elevata, from Sanibel Island. Photo by José H. Leal.