Diplostraca

Diplostraca Temporal range: Jurassic–Present PreꞒ Ꞓ O S D C P T J K Pg N [1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Branchiopoda
Subclass:	Phyllopoda
Superorder:	Diplostraca Latreille, 1829
Orders[2]
Anomopoda G.O. Sars, 1865 Ctenopoda G.O. Sars, 1865 Cyclestherida Sars G.O., 1899 Haplopoda G.O. Sars, 1865 Laevicaudata Linder, 1945 Onychopoda G.O. Sars, 1865 Spinicaudata Linder, 1945 Cladocera incertae sedis (temporary name)
Synonyms[2]
Cladocera Latreille, 1829 Eucladocera (no evidence for grouping together all other cladocerans as the sister taxon to the monotypic Haplopoda (Leptodora))

The Diplostraca or Cladocera, commonly known as water fleas, is a superorder of small, mostly freshwater crustaceans, most of which feed on microscopic chunks of organic matter, though some forms are predatory.^[2]

Over 1000 species have been recognised so far, with many more undescribed.^{[2][3][4][5][6]} The oldest fossils of diplostracans date to the Jurassic, though their modern morphology suggests that they originated substantially earlier, during the Paleozoic. Some have also adapted to a life in the ocean, the only members of Branchiopoda to do so, though several anostracans live in hypersaline lakes.^[7] Most are 0.2–6.0 mm (0.01–0.24 in) long, with a down-turned head with a single median compound eye, and a carapace covering the apparently unsegmented thorax and abdomen. Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats.