Collected from the Gambia, West Africa, Atlantic Ocean
The one on the left looks like Circomphalus foliaceolamellosus (Dillwyn, 1817). Live-taken specimens are usually quite frilly, but the frills are fragile, and beach-collected specimens often look like this one.
The others are Cardita ajar (Adanson, 1792)
Thank you very much for your help