Guide to Adult Caddisflies or Sedge flies

FSC Caddis adults AIDGAP is an identification guide to families of adult caddisflies in Britain. Identification follows to species level where possible.

Many moth recorders will have discovered caddisflies in their light traps, but perhaps not attempted identification. Caddisflies are also familiar to keen fly fishermen, who imitate them with artificial flies.

For people unfamiliar with the group, opening a dedicated identification book on caddisflies can seem intimidating. So this brief guide is a gentle first step. There is a photo of a representative species, along with useful features such as flight period and wing length. There are currently 199 species in the British Isles, with around 1400 species in Europe and over 12,000 worldwide.

This caddis adults guide is part of the FSC’s AIDGAP series (Aids to Identification in Difficult Groups of Animals and Plants). The aim of AIDGAP series is to produce handy keys appropriate for non-specialists from age 16+. Although written by specialists, all AIDGAP guides are field tested in draft form. As with all guides in the series, the Caddis adults AIDGAP underwent far-reaching testing before publication, by beginners and specialists alike. The author has revised this, the first published version, in light of testers’ experience.

Accurate identification of specimens is an significant part of biological fieldwork. Although popular groups such as wild flowers and butterflies are well-served, many other groups are ignored. Since 1976, the AIDGAP project has published over 40 straightforward and plainly written identification keys to many different groups of plants, animals and other taxa. In many cases a newly published AIDGAP guide has led to an immediate upsurge in the quantity and spread of biological records.