If you found a mollusc you have never seen before, how would

Last updated: 8/2/2022

If you found a mollusc you have never seen before, how would you know if it was a gastropod or bivalve? most gastropods have a single shell, bivalves have two shells gastropods have a foot, bivalves don't have a foot gastropods have a mantle, bivalves do not posses a mantle gastropods can live on land, but bivalves are only found in the water