Berkeley BioKeys: Invertebrates Home >> Invertebrates

Common Invertebrate Groups

Arachnids   class Arachnida
No wings, 8 legs. Includes spiders, mites, ticks, scorpions.

Insects  class Insecta
Biggest group. 6 legs. Head, thorax, abdomen. Includes flies, bees, ants, butterflies, beetles, etc.

Molluscs   phylum Mollusca
Soft bodies, often with a hard outer shell. Includes snails, slugs, clams, oysters, octopus.

Segmented Worms  phylum Annelida
Segmented worms. Includes earthworms and leeches.

Centipedes & Millipedes  class Myriapoda
Long body with many segments and many legs. Includes centipedes and millipedes.

Crustaceans  class Crustacea
Hard shell cover, two pairs of antennae. Includes crabs, shrimp, lobsters, barnacles.

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