Metridiidae

Metridiidae
Metridium senile
Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Anthozoa
Subclass:	Hexacorallia
Order:	Actiniaria
Family:	Metridiidae Carlgren, 1893

Metridiidae is a family of sea anemones in the order Actiniaria.

Members of the family Metridiidae are characterised by having a mesogloeal sphincter muscle and by the mesenterial arrangement, with the mesenteries not being divided into macronemes and microcnemes. The acontia typically have microbasic b-mastigophors and microbasic amastigophors, though the latter are not always present in adults.

The following three genera are recognised by the World Register of Marine Species (WoRMS):

Of these genera, Metridium is the most speciose while Isometridium and Paraisometridium are monotypic taxa.

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