FSC Freshwater invertebrates AIDGAP is an identification guide for ponds, lakes, streams and rivers in Britain and Ireland. Identification goes to at least the family level.
The guide is a bridge between popular colour identification guides and more specialist works. Users move through a series of dichotomous keys. But the authors have avoided specialist terminology whenever possible.
You don’t need any special equipment beyond a net, white tray and hand lens. The author has spent many years of leading fieldwork, so has chosen characters visible on living specimens. These include easily observed animal behaviour where this is a useful clue. As a result, the key will work with samples collected in a standard pond net. The author has excluded most animals less than 2 mm long, including all Protozoa, Rotifera and Nematoda. However, some groups, like the planktonic crustaceans, are covered, because they can be found in such quantities as to make this arbitrary guideline seem unreasonable.