American Bullfrog

Lithobates catesbeianus

Summary 2

The American bullfrog (Lithobates catesbeianus), often simply known as the bullfrog in Canada and the United States, is an aquatic frog, a member of the family Ranidae, or “true frogs”. This species has traditionally been classified as Rana catesbeiana, however the classification has been changed to Lithobates due to paraphyly in Ranidae.

This is a non-native, introduced species in California.

This frog has an olive green back and sides blotched with brownish markings and a whitish belly spotted with yellow or grey. The upper...

Description 3

This frog is the largest in North America and is distinguished by lacking dorsolateral folds and having very large tympanums, larger than the eye in males. The tips of the fingers and toes are blunt. The webbing is well developed. The skin on the back of this species is rough with random tiny tubercles. There is no dorsolateral fold, but there is a prominent supratympanic fold. The mean snout to vent length for males is 152 mm (range 111-178) and for females it is 162 mm (range 120-183). The males have pigmented nuptial pads. The vocal openings are at the corner of the mouth.The dorsum is green, with or without a netlike pattern of gray or brown on top. The venter is slightly white, sometimes mottled with gray or yellow. Coloration varies widely depending on the locality of the bullfrog (Conant and Collins 1975).

See another account at

Sources and Credits

  1. (c) copepodo, some rights reserved (CC BY-NC-ND),
  2. Adapted by Michelle S. Koo from a work by (c) Wikipedia, some rights reserved (CC BY-SA),
  3. (c) AmphibiaWeb © 2000-2011 The Regents of the University of California, some rights reserved (CC BY),

More Info

iNat Map

Iucn status Least_Concern
Taxonomy:family Ranidae