Key to the Rodentia
           
 
 Ear 75 percent or more of hind foot length
   
Ear less than 75 percent of hind foot length 
 
           
Artiodactyla
 - 
Carnivora
 - 
Chiroptera
 - 
Didelphimorphia
 - 
Insectivora
 - 
Lagomorpha
 - 
Rodentia
 - 
Xenarthra
Scientific Names - Common Names