Musculus discors, or the discord mussel, is a species of bivalve mollusc in the family Mytilidae.

It can be found along the Atlantic coast.

In North America it ranges from Labrador to Long Island Sound,[1] around Alaska and in northern European waters, including around most of the coast of Britain.

[2] It is a global IUCN Red List species, and of national conservation importance within Great Britain.

This Mytilidae-related article is a stub.