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Checklist of Amphibian Species and Identification Guide

American Bullfrog, Rana catesbeiana


The Bullfrog is a large frog attaining lengths in excess of 6 inches. The dorsal color is usually a dull green, but may be brownish. Some specimens are dark gray to black. There are usually no markings on the dorsal surface. The ventral surface is often ranges between shades of white to yellow. They have little to no dorsolateral ridges. Bullfrog
Bullfrog Like many species of Rana, the tympanic membrane is helpful in determining the gender of the individual. In females, the membrane will be roughly equal to the size of the eye and in males the membrane will be considerably larger.
The Bullfrog is native to the central and eastern United States and the southern portions of Ontario and Quebec. The Bullfrog has been introduced to many areas in the western United States creating patchy populations. Consult a field guide for a better view of the areas where Bullfrogs are known to occur in these western states. Bullfrog
Bullfrog Bullfrog Range

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