Family Ranidae: Riparian Frogs And True Frogs
Order Anura: Frogs And Toads
Description: The typical or ?true? frogs, mostly medium to large-sized, with long rear legs, smooth, moist skins, well-developed webbing between the toes, and low-pitched ?croaking? calls. Only one genus is found in the United States. All Illinois species but the bullfrog have an evident fold of skin extending along each side on the back (dorsolateral fold or ridge). Most eat anything small enough to swallow, including insects, worms, crayfish, spiders, other frogs, and fish. Most are highly aquatic and rarely found away from water. Breeding takes place during early to late summer in almost any kind of permanent water body. In some species -- notably the bullfrog and green frog -- tadpoles overwinter to transform throughout their second summer.
Family Ranidae, Riparian Frogs And True Frogs
Key Characteristics: Dorsal lateral ridge wraps around tympanum (does not run down back); snout blunt.
Habitat: Inhabits virtually any permanent body of water.
Habitat: Ponds, lakes, streams, swamps, and other permanent or semi-permanent water bodies. They are more tolerant of sparsely-vegetated habitats than are Bullfrogs.
Habitat: Ponds, creeks, and marshes in northern Illinois; in central and western parts of the state found in cold springs and rocky, high-gradient streams (often in cave streams along the Mississippi river bluffs). Avoids warm sluggish water.
Key Characteristics: Dark mask on side of head extending backward from the eye; tan to black in coloration; unspotted back
Habitat: Restricted to fairly large tracts of mesic coniferous, mixed, or deciduous forest where vernal pools are present.