Key to Australian Freshwater and Terrestrial Invertebrates

Phylum Arthropoda, Subphylum Crustacea

Key to the Classes and Orders of Crustacea

Common name: crustaceans

Crustaceans are an extremely diverse group including animals such as crabs, lobsters, isopods, shrimp and barnacles. Like all arthropods, crustaceans have a segmented body and segmented limbs and a thick chitinous cuticle called an exoskeleton. Crustaceans have three major body segments: a head with two pairs of antennae, a thorax from which more than four pairs of legs are attached, and an abdomen. They can range in size from microscopic plankton (< 1 mm long) to giant crabs (the Japanese spider crab has a leg span 4.3 m), and have adapted to nearly all environments. Most crustaceans live in marine or freshwater habitats, but some groups are completely terrestrial. There are over 8,000 described species of crustacean in Australia, and almost 70,000 species known worldwide. Crustaceans are grouped into five classes: Branchipoda, Ostracoda, Remipedia, Maxillopoda and Malacostraca.

Malacostraca - Decapoda - Austrothelphusa transversa
Image credit: � Stephen Zozaya
used with permission

Malacostraca - Decapoda - Rhynchocinetes sp.
Image credit: Richard Ling
used under a Creative Commons Attribution-NonCommercial-ShareAlike license

Malacostraca - Decapoda - Decapoda - Hermit crab
Image credit: Vanessa Pike-Russell
used under a Creative Commons Attribution-NonCommercial-NoDerivs license

Malacostraca - Amphipoda - blind amphipods from the Pilbara, Western Australia
Image credit: Bill Humphries � Western Australian Museum
used with permission

Malacostraca - Bathynellacea
Brevisomabathynella uramurdahensis
Image credit: � Kym Abrams, used with permission

Branchiopoda - Conchostraca - Paralimandia badia
Image credit: � Brian Timms, Honorary Research Associate, Australian Museum, Sydney
used with permission

Branchiopoda - Notostraca - Triops australiensis
Image credit: � Brian Timms, Honorary Research Associate, Australian Museum, Sydney
used with permission

Malacostraca - Isopoda - terrestrial isopod from Mt Gibson, Western Australia
Image credit: Mark Harvey � Western Australian Museum
used with permission

Branchiopoda - Cladocera - Simocephalus vetulus
Image credit: � Daniel Stoupin, used with permission
Microworlds Photography

References and further information

ABRS Australian Faunal Directory: Crustacea
Atlas of Living Australia: Crustacea
Encyclopedia of Life: Crustacea
Tree of Life: Arthropoda: Crustacea
Australian Museum, crustaceans
Guide to Marine Zooplankton of South Eastern Australia
Lucid Key to the families of aquatic crustaceans
Marine Education Society of Australasia, crustaceans

This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Australia License.