Leopard Frogs are medium to large slender nocturnal frogs growing up to five inches in length. The ranges of the Southern Leopard Frog and the Rio Grande Leopard Frog overlap in Central Texas.
Both the Southern and Rio Grande Leopard Frogs are pale brown to green with irregular dark spots. The Rio Grande Leopard Frog is distinguished to some extent by the dark spots being outlined by a lighter color.
The Rio Grande Leopard Frog has russet or reddish brown dorsolateral ridges which are broken near the hind legs. The Southern Leopard Frog has very light colored dorsolateral ridges continuous to the groin.
The ear drum, or tympanum of the frogs differ in that there is a light spot on the tympanum of the Southern Leopard Frog which is missing on the Rio Grande Leopard Frog.