Hooked Mussel

Ischadium recurvum

"Ischadium" is a monotypic genus of mussels in the family Mytilidae. The sole species is "Ischadium recurvum", known as the "hooked mussel" or "bent mussel". It can be found along the Atlantic coast of North America, ranging from Cape Cod to the West Indies.
Ischadium recurvum This is a picture of a Ischadium recurvum at Ferry Point Park on Kent Island in Queen Anne's County, Maryland. Geotagged,Ischadium,Ischadium recurvum,United States,Winter

Habitat

They are often found growing on Eastern oysters, either intertidal or subtidal. They also attach to other hard substrates, including artificial reefs and dead shells of brackish water clams, Rangia cuneata.

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Taxonomy
KingdomAnimalia
DivisionMollusca
ClassBivalvia
OrderMytilida
FamilyMytilidae
GenusIschadium
SpeciesI. recurvum