Metridiidae

Metridiidae is a family of sea anemones in the order Actiniaria.^[2]

Metridiidae
Metridium senile
Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Subphylum:	Anthozoa
Class:	Hexacorallia
Order:	Actiniaria
Superfamily:	Metridioidea
Family:	Metridiidae Carlgren, 1893[1]

Characteristics

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.^[1]

Genera

The following genera are recognised by the World Register of Marine Species (WoRMS):^[3]

• Metridium Blainville, 1824
• Paraisometridium Zamponi, 1978

Of these, Metridium is the most speciose while Paraisometridium is monotypic.