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Checklist of Amphibian Species and Identification Guide

Eastern Narrow-mouthed Toad, Gastrophryne carolinensis


Eastern Narrow-mouthed Toad
The Eastern Narrow-mouthed Toad is a small toad-like amphibian attaining lengths of 1.5 inches. Narrow-mouthed Toads are not, however, related to the true toads (genus Bufo) and in contrast to them have smooth, moist skin, which is why North American microhylids (Microhylidae) are referred to as Narrow-mouthed Frogs. These three species can be distinguished from other anurans by their body shape which forms a triangle with a very small pointed head. Unique to them is a fold of skin found directly behind the eyes as seen in this photo. Another distinguishing feature is their lack of an external eardrum or tympanum which, in North America, is a characteristic shared only by the Tailed Frog (Ascaphus truei). The underside of the Eastern Narrow-mouthed Toad is heavily mottled, which distinguishes it from the Great Plains Narrow-mouthed Toad which has a nearly unmarked ventral surface. The Sheep Frog is also very similar (it, too, has a mottled belly), but can be ditinguished from the Narrow-mouthed Toads by the presence of two tubercles or "spades" on the heel of the back foot — the Narrow-mouthed Toads have only one. Sheep frogs also have a light line down the center of the belly.
Eastern Narrow-mouthed Toad Eastern Narrow-mouthed Toad
The color of the Eastern Narrow-mouthed Toad varies and can be light tan, gray, brown or reddish, and an individual can change its color depending on the background of habitat that it is in. By observing the coloration of the throat region, you can determine the gender of the individual. Males have a darkly pigmented throat region whereas females do not. Breeding occurs from April to October in the south, during the summer in the north, and is initiated by rain. The eggs are laid in a thin floating film and hatch in a few days, tadpoles develop into frogs within one month. They are very nocturnal and feed pimarily on ants. Click here to hear the call of an Eastern Narrow-mouthed Toad from southwest Florida (recording by Ted Owens).
The Eastern Narrow-mouthed Toad ranges from southern Missouri to eastern Texas, south and 
east to the coast where they range as far north as southern Maryland.

Notice:  All images contained hereafter are the property of the said photographer. They are not to be reproduced, copied, printed, stored, or distributed without written permission of the photographer.

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