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Which major animal groups belong to the phylum Mollusca?
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mollusk
Mollusk shell classification chart, c. 1861.
The phylum Mollusca is a diverse group of soft-bodied invertebrates that includes several major classes. These animals are typically characterized by a soft body often protected by a calcium carbonate shell secreted by a mantle.12
The major groups belonging to the phylum Mollusca include:
- Aplacophora: Worm-shaped mollusks that lack shells, including the Caudofoveata and Solenogasters.12
- Polyplacophora: Commonly known as chitons, these are characterized by eight serial shell plates.12
- Monoplacophora: Cap-shaped mollusks, also known as neopilinids.12
- Bivalvia: Includes clams, mussels, scallops, oysters, shipworms, and cockles.12
- Scaphopoda: Known as tusk shells, these have tubiform or barrel-shaped shells.12
- Gastropoda: A large group comprising limpets, snails, and slugs.12
- Cephalopoda: Includes nautiluses, cuttlefishes, squids, and octopuses.12