Myoida

Myoida
A live individual of the soft-shelled clam, Mya arenaria
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Subclass:	Heterodonta
Order:	Myoida Stoliczka, 1870
Superfamilies and Families
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Myoida is an order of saltwater clams, marine bivalve molluscs in the subclass Heterodonta. The order includes such bivalves as soft-shell clams, geoducks, and shipworms.

These are burrowing molluscs, with well-developed siphons. The shell is relatively soft, and lacks a nacreous layer. Some species have a single cardinal tooth.

Superfamilies and families within the Myoida include:

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