noun
- any member of the crustacean order Anostraca, characterized by an elongate trunk with more than 20 segments and the absence of a carapace, typically found swimming ventral side up in fresh water.
noun
- any small freshwater branchiopod crustacean of the genera Chirocephalus, Artemia, etc, having a transparent body with many appendages and habitually swimming on its back: order Anostraca