Four-toed Salamander adults are small and slender terrestrial salamanders. Their overall body coloration is a rusty brown or dark maroon with legs and tail fading to a lighter shade of red or orange. Tail has an obvious constriction at its base. A dark spotting pattern is present dorsally along the body and tail. This is apparent in varying intensities between individuals. Flanks and lower head sport a silvery mottling. Belly is a stark white with contrasting black spots; a characteristic unique to this species. They are also the only salamander species in Illinois to have rear feet with 4 toes, giving them their name.
This species lives amongst the forest floor within upland hardwood forests. They can be found under logs and leaf material in March before migrating to breeding sites. Breeding sites consists of fishless seeps and marshes where thick moss growth overhanging water persists. After migrating to these locations in April, gravid females climb into this moss and deposit their eggs. Suitable moss clumps are usually in association with vegetative hummocks and woody debris. Females usually remain in their nest with the clutch until the brood hatches. Once hatched, larvae wiggle out of this moss and drop into the underlying water below where they remain in a gilled aquatic larval stage for a month before transforming into adulthood.
The combination of high quality seepages within a close proximity to upland hardwood forests are mandatory requirements for the continued survival of this species.