Phylum Mollusca (4)
Snails first appear in the fossil record in earliest Cambrian strata (the Tommotian stage), but they did not become abundant until the Ordovician. Terrestrial and freshwater snails first appeared in the Devonian.
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Phylum Mollusca (4)
Snails first appear in the fossil record in earliest Cambrian strata (the Tommotian stage), but they did not become abundant until the Ordovician. Terrestrial and freshwater snails first appeared in the Devonian.