Gastrophryne carolinensis

Gastrophryne carolinensis, the eastern narrow-mouthed toad, is a species of microhylid frog. It is a relatively small, toad-like amphibian found in damp, shady habitats. The species is highly fossorial, and feeds primarily on ants. These North American microhylids (Family: Microhylidae) are distinguished from true toads (genus Bufo), and other anurans by their moist, smooth skin, their lack of eardrums or tympana, their distinguishable squat body shape, and the unique fold of skin superior to their eyes. It is found in the United States, from southern Maryland to the Florida Keys, west to Missouri and Texas. While not a true toad, it is so called because it is terrestrial. Gastrophryne carolinensis belongs to one of the largest anuran families, the microhylids. No subspecies are currently recognized. The eastern narrow-mouthed toad is relatively small, growing to a maximum length of 53 mm (2.1 in). It has an oval-shaped body and a narrow head with a pointed snout. They vary in color from brown and grey to green, often with black and white spotting.Gastrophryne carolinensis toads have a typical teardrop-shaped body that is characteristic of members of the family Microhylidae. Though its morphology lacks a tympanum (eardrum), the subgular vocal sac is clearly visible. The skin of G. carolinensis is smooth and without ridges or warts. Yet, the skin is extremely tough, which most likely protects them from the ants upon which they feed. The color of the toad can change its color depending on its activities and environment. The colors on its sides are generally faded, but its dorsum is dark and broad with various light or dark spots, mottling, or patches that cover the light strip along its middorsal area. Its abdomen is generally highly mottled, but its ventral surface is nearly light or unmarked. The venters of certain arrow-mouthed toads in the Great Plains are generally unmarked, or virtually so, while those of eastern toads are strongly pigmented. Its legs are generally stubby, short, and heavy, and the tips of the toes are round and tapered. As with the Leptodactylidae, the toes are absent of webbing or toe pads. However, the heels on the back feet have one “spade” or tubercle for digging. The sex of the eastern narrow-mouthed toad can easily be determined by the characteristic sexual dimorphism. The color of the throat region for males is dark and highly pigmented, while the female throat is absent of this discriminate coloring. The narrow-mouthed toad can reach elevations up to 550 m (1,800 ft). They are generally absent from most Blue Ridge Mountains and the Appalachian Mountains.