Daphniidae

Daphniidae
Daphnia pulex
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Branchiopoda
Order:	Cladocera
Suborder:	Anomopoda
Family:	Daphniidae Straus, 1820

Daphniidae is a family of water fleas in the sub-order Anomopoda.

Members of the family Daphniidae differ from other, similar cladocerans, such as Macrotrichidae and Moinidae, in that the antennae of females are short and immobile.

The feeding mechanism of the members of the family Daphniidae differs from that of Macrotrichidae in allowing the animals to engage in filter-feeding, rather than having to scrape food from a surface. They have evolved to fill a number of different ecological niches. Scapholeberis and Megafenestra contain species adapted to living around the surface film; Simocephalus species cling to objects while filter-feeding; others have developed a pelagic lifestyle.

The family Daphniidae contains 121 species in five genera:

The members of the family Moinidae may also be placed among the Daphniidae.

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