The second volume of this book series synthesizes nomenclature, systematics, and descriptions of North American mammal species. Clear, simple and illustrated identification keys are provided to make knowledge of mammals easier and facilitate the training both students and professionals in the field, including readers without extensive experience. Descriptions of the different species are provided up to Order, highlighting the diagnostic features that allow identifying them promptly while the reader learns how to make subsequent identifications without having the book at hand. Each species comes with potential distribution maps based on existing records in the main museums of North America. The book includes the description, characteristics and distribution maps of the 781 species with range in the North America subcontinent.