Identifying freshwater and brackish mollusc species

I've just found this dichotomous key by Brian Eversham. If you're looking for something to identify your freshwater snails that's accessible online, that might be a good place to start (the photos look rather good). There are lots of useful identification links at the end of it too.

Amongst the molluscs, you'll only find Gastropods on land, but our freshwater species include Bivalves as well (which Mr Eversham, above, possibly wisely excludes, as they are notoriously awkward). The two books below do include them though.

some pearl mussels - but don't get any ideas, it's illegal to even take them out of the water without a license as they're endangered and protected by law. CC image by MrKimm

Collins Photo Guide 'Lakes, Rivers, Streams and Ponds' by Fitter and Manuel has a mollusc section. There are dichotomous keys and you can usually reach a species. You can borrow this from OJ17, or I think there are some in the library.

Janus's book "The Young Specialist looks at Molluscs"  includes freshwater snails, and also has a special section on freshwater bivalves which explains the mysterious business of looking at the characteristics of the hinge and its teeth. This book has a bit of a silly title (and the species names need updating) but I do find the pictures and descriptions good, especially in tandem with other resources. It's out of print but usually pretty cheap second hand. You can have a look at my copy in the lab too.

The Conchological Society of Great Britain and Ireland has lists of species that may be found in particular habitats (for example, rivers, streams, canals, standing water and marshy areas). Unfortunately the species names don't link to any more information, but it may give you some inspiration about where to look. The Conchsoc does have an online key for identifying British and Irish freshwater and brackish-water snails (this doesn't include bivalves).

The names will be woefully out of date, but T.T. Macan's 'British Fresh- and Brackish-Water Gastropods' is an oft-recommended book. I've not tried it out so perhaps you can give me your opinion. It's published by the Freshwater Biological Association and we have a copy.

Check for up-to-date species names with the Natural History Museum's UK species database.

You might want to look at my suggestions for identifying terrestrial species also.