It varies from green to brown in dorsal color, with large, dark, circular spots on its back, sides, and legs.

They are found in permanent ponds, swamps, marshes, and slow-moving streams throughout forest, open, and urban areas.

This species was once quite common through parts of western Canada and the United States until declines started occurring during the 1970s.

They eat a wide variety of animals, including crickets, flies, worms, and smaller frogs.

One such molecule, called ranpirnase (onconase), is in clinical trials as a treatment for pleural mesothelioma and lung tumors.

[12] The northern leopard frog has been a preferred species for making discoveries about basic properties of neurons since the 1950s.

The neuromuscular junction of the sciatic nerve fibers of the sartorius muscle of this frog has been the source of initial data about the nervous system.

Northern leopard frogs occur from Great Slave Lake and Hudson Bay, Canada, south to Kentucky and New Mexico, USA.

[20][21] It is also found in Panama, where it is endemic to the central cordillera and western Pacific lowlands, although this is most likely an undescribed species.