crustacean

Introduction

CE5

Internal anatomy of a female crayfish, representative of the class Crustacea

crustacean krŭstāˈshən [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.

Sections in this article:

Introduction
Classification
Crustacean Anatomy
Types of Crustaceans

See more Encyclopedia articles on: Zoology: Invertebrates