Key to the Rodentia
           
 
 Tail obviously longer than head and body; last upper molar with worn cusps forming an E-shape (Fig. 52a)
   
 Tail shorter than (may be equal to) head and body length; last upper molar with worn cusps forming a C-shape
(Fig. 52b)
 
           
Artiodactyla
 - 
Carnivora
 - 
Chiroptera
 - 
Didelphimorphia
 - 
Insectivora
 - 
Lagomorpha
 - 
Rodentia
 - 
Xenarthra
Scientific Names - Common Names