Key to the Herpetofauna of the Continental United States and Canada

Six hundred and eighty-five native amphibians and reptiles are now recognised across the continental United States and Canada, up from 545 when this key first appeared in 1998, along with 67 established non-native species. Robert Powell's third edition catches up with that growth, much of it driven by molecular work that has redrawn species boundaries, and it works the way a good key should: step by step, through features you can actually see.

Those features are shown in 295 clear line drawings of colour patterns and body structures, and nine maps chart the ranges of species recognised since the latest Peterson Field Guides. Generous annotations set out where taxonomists still disagree, and the list of literature cited has grown. A dependable companion for students, teachers and anyone who wants to put a precise name to the salamander under the log.