Identification
There are three main identification keys around that are used.
Southwood & Leston (1959). Land & Water Bugs of the British Isles
Still in use today excellent ecological and behaviour information
A.A. Savage. (1989) Adults of the British Aquatic Hemiptera Heteroptera. A key will ecological notes.
A great study especially Corixidae.
Nau. B.S. (2010)Keys to the Aquatic and Semi-aquatic Hemiptera. Unpublished.
This is really well put together and concise including all the current UK species.
These keys are still valid today but as publications are more colourful these days i have started to put together an id guide and family keys with pictures by Tony Cooke the current National Recorder. I have attached these on the home page, ( https://sites.google.com/site/northantswaterbugs/home ) feel free to download and use and i would be happy to receive any comments to improve them or any fresh specimens of bugs missing so we can photograph.