The pickerel frog (Lithobates palustris, formerly Rana palustris) is a small North American frog, characterized by the appearance of seemingly "hand-drawn" squares on its dorsal surface.
The pickerel frog is a medium sized gray or tan frog marked with seven to twenty-one irregular rectangular dark brown spots which are oriented in two columns down its back. The distinctive rectangular spots of the pickerel frog may blend together to form a long rectangle along the back. All leopard frogs have circular spots. In addition, pickerel frogs have prominent dorsolateral ridges that are unbroken. Another important distinguishing mark is the orange or yellow flash pattern found on the inner surface of the hind legs of pickerel frogs. The frog must be picked up to examine this, as the legs cover the coloration otherwise. The plains leopard frog (Lithobates blairi) exhibits this coloration as well, but the dorsolateral ridges are interrupted and inset medially in that species. The front toes of pickerel frogs are not webbed, a morphological characteristic for some frogs of the genus Rana and some frogs of the genus Lithobates. This allows pickerel frogs to be fit for terrestrial life.
0276ModifierDxOAmphibiensEtatsUnisFrogsGrenouille des maraisGrenouillesKettle Pond State parkLithobates palustrisPaysPickerel frogState ParkUSAUnited States of AmericaVermontanimauxvertébrés