Cladocera

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Cladocera
Daphnia pulex
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Branchiopoda
Subclass: Phyllopoda
Order: Cladocera
Latreille, 1829
Suborders

Cladocera is an order of small crustaceans commonly called water fleas. Around 620 species have been recognised so far, with many more undescribed.[1]

They are everywhere in inland aquatic habitats, but rare in the oceans.[2] Most are 0.2–6.0 mm (0.01–0.24 in) long, with a down-turned head, and a carapace covering the thorax and abdomen.[3] There is a single median compound eye.[2] They swim with jerking flea-like movements.

Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction. The sexual reproduction produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats.[4]

References[change | edit source]

  1. L. Forró N.M. Korovchinsky, A.A. Kotov & A. Petrusek (2008). Global diversity of cladocerans (Cladocera; Crustacea) in freshwater. In Estelle V. Balian, Christian Lévêque, Hendrik Segers & Koen Martens. "Freshwater animal diversity assessment" (PDF). Hydrobiologia. Developments in Hydrobiology 198 595 (1): 177–184. doi:10.1007/s10750-007-9013-5. ISBN 978-1-4020-8259-7. http://decapoda.nhm.org/pdfs/27704/27704.pdf. doi:10.1007/978-1-4020-8259-7_19
  2. 2.0 2.1 Denton Belk (2007). "Branchiopoda". In Sol Felty Light & James T. Carlton. The Light and Smith Manual: intertidal invertebrates from Central California to Oregon (4th ed.). University of California Press. pp. 414–417. ISBN 9780520239395. http://books.google.co.uk/books?id=64jgZ1CfmB8C&pg=PA416.
  3. Douglas Grant Smith & Kirstern Work (2001). "Cladoceran Branchiopoda (water fleas)". In Douglas Grant Smith. Pennak's freshwater invertebrates of the United States: Porifera to Crustacea (4th ed.). Wiley. pp. 453 488. ISBN 9780471358374. http://books.google.co.uk/books?id=GqIctb8IqPoC&pg=PA468.
  4. Ellen Decaestecker, Luc De Meester & Joachim Mergaey (2009). "Cyclical parthenogeness in Daphnia: sexual versus asexual reproduction". In Isa Schön, Koen Martens & Peter van Dijk. Lost sex: the evolutionary biology of parthenogenesis. Springer. pp. 295–316. doi:10.1007/978-90-481-2770-2_15. ISBN 9789048127696. http://books.google.co.uk/books?id=GaWD_OtE0AMC&pg=PA296.