crustacean, Zoology: Invertebrates

Related Category: Zoology: Invertebrates

crustacean[krustA´shun] Pronunciation Key, primarily aquatic arthropod of the subphylum Crustacea. Most of the 44,000 crustacean species are marine, but there are many freshwater forms. The few groups that inhabit terrestrial areas have not been particularly successful in an evolutionary sense; most require very humid environments in order to survive.