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American Bullfrog

Lithobates catesbeianus

Summary 4

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

Diagnosis 5

The dorsal (upper) surface of the bullfrog has an olive-green basal color, either plain or with a mottling and banding of grayish brown. The ventral (under) surface is off-white blotched with yellow or gray. Often, a marked contrast in color is seen between the green upper lip and the pale lower lip.[1] The teeth are tiny and are useful only in grasping.[2] The eyes are prominent with brown irises and horizontal, almond-shaped pupils. The tympani (eardrums) are easily seen just behind the eyes and the dorsolateral folds of skin end close to them. The limbs are blotched or banded with gray. The fore legs are short and sturdy and the hind legs long. The front toes are not webbed, but the back toes have webbing between the digits with the exception of the fourth toe, which is unwebbed.[1]

Bullfrogs are sexually dimorphic, with males being smaller than females and having yellow throats. Males have tympani larger than their eyes, whereas the tympani in females are about the same size as the eyes.[1] Bullfrogs measure about 3.6 to 6 in (9 to 15 cm) from snout to vent. They grow fast in the first eight months of life, typically increasing in weight from 5 to 175 g (0.18 to 6.17 oz),[3] and large, mature individuals can weigh up to 500 g (1.1 lb).[4] In some cases bullfrogs have been recorded as attaining 800 g (1.8 lb) and measuring up to 8 in (20 cm) in length.[3][5]

Conservation 5

They are invasive and are likely hurting Hawaii's ecosystem.

Sources and Credits 5

  1. Knapp, W. W. (2008-05-28). "Bullfrog – Rana catesbeiana". The Frogs and Toads of Georgia. Retrieved 2013-01-20.
  2. Cardini, F. (1974). Specializations of the Feeding Response of the Bullfrog, Rana catesbeiana, for the Capture of Prey Submerged in Water. M.S. Thesis, U. of Massachusetts, Amherst, MA
  3. Lutz, G.; Avery, J. "Bullfrog Culture". Southern Regional Aquaculture Center. Retrieved 2013-01-09.
  4. "ANIMAL BYTES- North American Bullfrog". Sea World. Retrieved 2013-01-09.
  5. "Rana catesbeiana". Fisheries and Aquaculture Department. Retrieved 2013-01-09.

Sources and Credits

  1. (c) copepodo, some rights reserved (CC BY-NC-ND), http://www.flickr.com/photos/63661371@N00/2838159004
  2. (c) Howard Patterson, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/74113421@N03/36247860116/
  3. (c) Gabriel Legaré, some rights reserved (CC BY-SA), https://www.flickr.com/photos/experidoum/4853670107/
  4. Adapted by calebcam from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Lithobates_catesbeianus
  5. (c) calebcam, some rights reserved (CC BY-SA)

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