Guide to identifying common freshwater invertebrate groups

Diagrams of various freshwater invertebrates

This is a beginner's guide to the common groups of freshwater invertebrates found in Britain.

It is designed to help you differentiate broad groups of common freshwater invertebrates, principally to Order level, although some groups are broken down slightly further than this to differentiate groups a beginner will commonly encounter.

The guide is split into two sections, covering the insects and non-insect invertebrates separately.

On each page you will find:

  • an annotated photograph of common invertebrates within this group, highlighting key characteristics
  • a simple colour coded illustration highlighting the key characteristics
  • notes on which groups could cause confusion

At the end of the guide you will find:

  • a convenient summary table of identification characters for each of the groups covered
  • information on where to go next, to improve your identification invertebrates for each of the groups covered

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Related guides

Common UK insect and other terrestrial invertebrate groups

A beginner's guide to the common groups of terrestrial invertebrates found in Britain. Covers insects and non-insect invertebrates separately.