What is the water flea called? - briefly
The organism commonly referred to as the water flea is the crustacean «Daphnia». It belongs to the order Cladocera.
What is the water flea called? - in detail
The crustacean referred to as «water flea» belongs to the genus Daphnia. It is a small, planktonic organism found in freshwater habitats worldwide.
Taxonomic classification:
- Kingdom : Animalia
- Phylum : Arthropoda
- Subphylum : Crustacea
- Class : Branchiopoda
- Order : Cladocera
- Family : Daphniidae
- Genus : Daphnia
Key morphological features include a transparent carapace, large compound eyes, and antennae adapted for locomotion. Individuals typically measure 0.2–5 mm in length, with size varying among species and environmental conditions.
Reproduction occurs primarily by cyclic parthenogenesis: females produce clonal offspring asexually under favorable conditions, while sexual reproduction is triggered by stressors such as crowding or temperature shifts. The resulting resting eggs, called ephippia, remain dormant until conditions improve.
Ecologically, Daphnia species serve as primary consumers of phytoplankton, bacteria, and detritus, thereby regulating algal populations and influencing water clarity. They also constitute a major food source for fish larvae, amphibian tadpoles, and larger invertebrates.
Common species include Daphnia magna, noted for its relatively large size and use in toxicological testing, and Daphnia pulex, whose genome was the first crustacean genome to be fully sequenced.
In summary, the organism commonly identified as «water flea» is scientifically named Daphnia, a genus of freshwater cladocerans distinguished by specific taxonomic placement, morphological traits, reproductive strategies, and ecological functions.