Key to the Rodentia
           
 
 Size large, head and body 250 mm or more; tail long, scaly, and vertically compressed; hind feet webbed; greatest length of skull more than 30 mm
   
 Size much smaller, head and body 125 mm or less; tail short; greatest length of skull less than 30 mm
 
           
Artiodactyla
 - 
Carnivora
 - 
Chiroptera
 - 
Didelphimorphia
 - 
Insectivora
 - 
Lagomorpha
 - 
Rodentia
 - 
Xenarthra
Scientific Names - Common Names