Cladocera

REGION/HABITAT aaaa•found worldwide aaaa•the dominant 'plankton' found in freshwater habitats aaaa•open water aaaa•400 – 500 species FEEDING aaaa•phytoplankton and decaying organic material aaaa•marine species actively hunt REPRODUCTION aaaa•parthenogenesis - female produces eggs that develop into young without fertilization aaaa•sexual – under harsh conditions males are present in the population which fertilize the eggs CHARACTERISTICS aaaa•nicknamed the "water fleas" aaaa•bodies completely enclosed by the carapace aaaa•9 – 10 pairs of appendages aaaa•5 – 6 trunk limbs used for feeding and repiration aaaa•postabdomen attached to the abdomen aaaa•terminal pair of postabdominal claws aaaa•range in size from .3mm to 6mm Daphnia aaaa•laterally flattened aaaa•body is covered by a carapace aaaa•head and antennae are apparent aaaa•freshwater environments in open water aaaa•second pair of antennae used for locomotion aaaavertical migration – upward movement in the dark and downward migration during the day aaaa•important food source for fish and predatory insects

Pictures:

Daphnia
Daphnia Schödleri	Daphnia longispina

Helpful Links:

Taxonomy This site has details on the cladoceran body-plan.

Cladocera Overview Links to a site that overviews taxonomy, habitat, feeding and reproduction.