Illinois is situated in the midwestern United States. It is characterized by farmland, rolling hills, and wetlands, and has a continental climate with cool to cold winters, and hot, humid summers.
Habitats such as grassland and hardwood forest (often oak-hickory) are in abundance, but while wetlands such as swamps, marshes, and fens are present, many have been developed. The state also boasts access to lakes such as Lake Michigan and Carlyle Lake and has waterways such as the Illinois River and the Mississippi River flowing through it.
With this range of terrestrial and aquatic habitats, Illinois plays host to several salamander species, including the blue-spotted salamander, the eastern newt, and the lesser siren.
Illinois Salamanders
1) Blue-spotted salamander (Ambystoma laterale)
- Native to the northeastern US
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The blue-spotted salamander has a striking appearance, with a dark brown, black, or blue-black coloration spattered with pale blue specks, of which there are fewer on the back and more on the sides. This species has a wide head and typically grows to 7.6 – 12.7 cm (3 – 5 in) in length.
In Illinois, Ambystoma laterale can be found in the Northeastern Morainal Natural Division, where it occupies upland forests and wet meadows. Breeding pools are fishless and usually situated amongst oak or maple forest – the larvae remain in these pools until metamorphosis, at which point they leave and disperse into the surrounding terrestrial habitat.
In areas where the ranges overlap, the blue-spotted salamander may hybridize with the Jefferson salamander, which presents a conservation concern due to the genetic dilution of the two species. Preservation of the pure diploid population can be achieved by strict habitat management.
2) Spotted salamander (Ambystoma maculatum)
- Native to the eastern US
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The spotted salamander is large, reaching 10 – 25 cm (4 – 10 in) in length. Its coloration is dark brown or black with yellow spots along the back and sides, while the underside is gray. This species possesses glands in its back and tail which secrete a noxious substance – this makes the salamander unpalatable to a predator, thus affording them some protection.
Ambystoma maculatum can be found in southern Illinois, as well as in counties along the eastern edge of the state, and a handful of locations in the north. This species prefers hardwood or mixed forests with stagnant pools or swamps – research has found that individuals use the substrate to select an appropriate habitat.
When it comes to reproducing, females select the site at which they lay their eggs very carefully. Their preferences include deep water and dense aquatic vegetation – these factors increase the chances of survival of the offspring.
3) Eastern tiger salamander (Ambystoma tigrinum)
- Native to the Central US
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The eastern tiger salamander is the largest terrestrial salamander in North America, growing to lengths of up to 33 cm (1 ft 1 in). This species has a thick body and is black in color with bright yellow blotches. The underside is usually yellow or orange, although it may also display some darker pigmentation.
Ambystoma tigrinum can be found throughout Illinois, although its range has decreased due to disturbance by agriculture and development. The preferred habitat of this species includes upland and wetland habitats, with access to ponds for breeding and sandy loam soils for burrowing. As well as residing underground, individuals will often hide underneath logs.
During breeding season, there is much competition between males to find a mate. Research has found that large males are more successful and that females prefer males with longer tails.
4) Smallmouth salamander (Ambystoma texanum)
- Native to the US
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The smallmouth salamander is medium-sized, reaching around 17 cm (6.7 in) in length. Individuals have 14 – 16 costal grooves and are stockily built with short limbs. The coloration of this species is dark gray, black, or dark brown, with flecks of blue-gray across the dorsum. There may also be some pale flecks on the belly, although these are much sparser.
Ambystoma texanum is found throughout the southern half of Illinois – there may be a handful of populations further north, however these are few and far between. These salamanders reside in woodlands, rocky hillsides, pastures, and prairies, usually in close proximity to pools. Loss of wetland habitat for breeding is a serious threat to this species.
The larvae of the smallmouth salamander feed on a variety of invertebrate prey and may also occasionally resort to cannibalism. Research has found that they are incredibly sensitive to olfactory cues, and will seek cover if they detect the chemical cues of predators.
5) Jefferson salamander (Ambystoma jeffersonianum)
- Native to the northeastern United States
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The Jefferson salamander is long, reaching 12 – 21 cm (4.7 – 8.3 in) in length, with a slender build and relatively long limbs. This species is usually dark brown or gray in color and has blue flecks along the limbs and lower sides of the body, while the underside is typically paler gray in color.
In Illinois, Ambystoma jeffersonianum is restricted to Clark and Edgar counties, where it occupies upland deciduous forest, particularly beech-maple. This species has been found to consume slugs, snails, earthworms, and insect larvae. Individuals spend much of their time hiding in burrows or underneath logs and are rarely seen by humans except during the breeding season.
This species breeds in early spring, traveling to pools to deposit eggs and spermatophores. Selection of suitable breeding habitat is important – Jefferson salamanders have been found to prefer cooler, more turbid water with dense vegetation surrounding the pool.
6) Northern slimy salamander (Plethodon glutinosus)
- Native to the eastern and central United States
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The northern slimy salamander ranges from 11.4 – 20.3 cm (4.5 – 8 in) in length and has a slender build with a cylindrical tail. This species has 15 – 17 costal grooves and has a narrow head with large eyes. The coloration of the skin is blue-black with a scattering of white or gold flecks on the dorsum, while the underside is slightly paler in color.
Plethodon glutinosus is common in the southern half of Illinois, where it resides in deciduous or hemlock forests. Individuals spend much of their time hiding underneath logs or in burrows, emerging at night to forage on earthworms, snails, slugs, spiders, centipedes, and insects. Interestingly, this species has been shown to be negatively affected by non-native earthworm invasions, which cause a reduction in leaf litter, thus reducing the availability of prey species.
The northern slimy salamander’s name is due to a sticky secretion that it produces when threatened. This is hard to remove and aids in deterring predators, as it renders the salamander unhandleable.
7) Spotted-tail salamander (Eurycea lucifuga)
- Native to eastern North America
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The spotted-tail salamander is also known as the cave salamander. It grows to lengths of 10 – 20 cm (3.9 – 7.9 in) and has a slender build with a long tail – females are often larger than males. The dorsal skin can be bright orange, yellow, or red, and is covered in dark brown or black spots, while the belly is paler in color and tends not to display any markings.
Eurycea lucifuga is found in the southern tip of Illinois, in Union, Johnson, Pope, Hardin, Alexander, Pulaski, and Massac counties. This species is often found in the ‘twilight zone’ of caves, which is the area between the mouth of the cave and the point where light no longer reaches. Individuals can also be found in wooded areas or along rocky streams.
Common prey items of the spotted-tail salamander include pillbugs, seed shrimp, and flies and their larvae. Due to often foraging under the cover of darkness, this species uses tactile and chemical cues to detect its prey.
8) Eastern newt (Notophthalmus viridescens)
- Native to eastern North America
- Family: Salamandridae
- Order: Urodela
- Conservation status: Least concern
The eastern newt grows to 7 – 12.5 cm (2.8 – 5 in) in length and is characterized by moist, rough skin. This species has three distinct life phases: larval, eft, and adult. During the eft phase, it is terrestrial and has bright orange-red skin, while in the adult phase, it has yellow or green-brown skin with small red dots.
Notophthalmus viridescens can be found in the north and south of Illinois and is absent from the center of the state. The adults and larvae reside in freshwater lakes, ponds, and marshes, while the efts can be found amongst leaf litter. This species consumes ostracods, copepods, dipterans, and ephemeropterans.
Eastern newts produce tetrodotoxin, a neurotoxin that functions as a chemical defense against predators such as fish and crayfish. However, it does not deter every predator – bullfrogs will still readily feed on the newts.
9) Common mudpuppy (Necturus maculosus)
- Native to eastern North America
- Family: Proteidae
- Order: Urodela
- Conservation status: Least concern
The common mudpuppy is a large, neotenic salamander that grows up to 48 cm (1 ft 7 in) in length. It has a gray-brown dorsum and a pale gray underside, with small black spots on the belly. Being permanently aquatic, this species has large external gills which are red in color, and its eyes are small and lidless.
Although Necturus maculosus was once found throughout Illinois, it has declined in recent years and is now restricted to a handful of rivers and streams, as well as Lake Michigan. The most prevalent threats to this species are sedimentation and pollution, although they may also suffer habitat degradation.
Common mudpuppies consume a varied diet including mollusks, leeches, insects, crayfish, fishes, and frogs. They detect their prey by vibrations, which are picked up by the lateral line, although it is visual and olfactory cues that trigger the snapping response.
10) Long-tailed salamander (Eurycea longicauda)
- Native to the Appalachian range of the US
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The long-tailed salamander ranges in length from 10 – 20 cm (3.9 – 7.9 in) and has a slender body, with a narrow head and long tail, which comprises over 60% of the total length. The coloration of this species is yellow, orange, or brown, with numerous black spots that form irregular lines down the dorsum. The underside is yellow or white with occasional dark flecks.
Eurycea longicauda can be found along the southwestern edge of Illinois, where it occupies slow-moving streams, fens, and swamps. As with many salamander species, individuals spend much of their time hiding underneath rocks, logs, or leaf litter. They are nocturnal foragers, usually pursuing earthworms or terrestrial insects.
Long-tailed salamanders breed anytime from fall through to spring, and while little is known about their courtship, it is thought that males and females rub their heads together ritualistically. The female lays between 60 – 110 eggs, usually depositing them on the undersides of submerged rocks.
11) Marbled salamander (Ambystoma opacum)
- Native to the eastern United States
- Family: Ambystomatidae
- Order: Urodela
- Conservation status: Least concern
The marbled salamander is heavy-bodied and is usually just 9 – 10.7 cm (3.5 – 4.2 in) in length. This species has incredibly distinctive coloration: pale crossbands and blotches over a dark brown or black body (females tend to have gray markings, while in males, the bands and blotches are white).
In Illinois, Ambystoma opacum can be found in the southern region of the state, from Marion County downwards. Populations have a preference for mesic forests, dry hillsides, and moist floodplains, although they migrate to wooded pools in the fall to reproduce. The position within a pool that the female selects to lay her eggs can influence the hatching rate and development of the larvae – eggs in shallower waters may be more susceptible to freezing temperatures or may perish if the pond dries out.
12) Southern two-lined salamander (Eurycea cirrigera)
- Native to the Southeast US
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The southern two-lined salamander is usually 6.4 – 9.5 cm (2.5 – 3.7 in) in length, although records of up to 11 cm (4.3 in) have been recorded. Individuals have a slender build with a long tail and fourteen costal grooves. Their skin is golden brown with a yellowish underside, and there are two dorsolateral stripes, one running from each eye down to the tail.
Eurycea cirrigera can be found along the southeastern edge of Illinois, often residing beside rocky brooks, seeps, or streams amongst mesic forests. This species feeds on a great variety of invertebrates, including coleopterans, collembolans, dipterans, and collembolans – it forages both terrestrially and aquatically, usually opting to go in the water when conditions are drier on land.
During breeding season, female southern two-lined salamanders lay their eggs underneath rocks, which often end up being concealed under a layer of algal growth. The young may remain in larval form for up to three years before undergoing metamorphosis.
13) Lesser siren (Siren intermedia)
- Native to the eastern United States and Mexico
- Family: Sirenidae
- Order: Urodela
- Conservation status: Least concern
The lesser siren is a purely aquatic salamander that grows to 18 – 68 cm (7.1 in – 2 ft 3 in) in length and has a slender build. Due to this species’ aquatic lifestyle, it has no hindlimbs, and the front limbs are very small – individuals also have external gills. This salamander is gray-green, olive, or black in color, with small markings visible on some individuals.
In Illinois, Siren intermedia can be found in the south of the state, and in a handful of counties in the west. They can commonly be found in lakes, ponds, and ditches, but if the water dries out, they can aestivate by forming a mucous cocoon. While in this state, the heart rate and oxygen consumption both fall.
The lesser siren is thought to forage nocturnally, consuming crustaceans, insects, worms, and snails. Research has found that this species is likely to use chemical cues in searching for prey, rather than visual cues – this may explain why sirens have such small eyes.
14) Northern dusky salamander (Desmognathus fuscus)
- Native to eastern North America
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The northern dusky salamander, also known as the spotted dusky salamander, grows to lengths of 6.4 – 12.7 cm (2.5 – 5 in) and has a stout build. This species has fourteen costal grooves and is brown in color, with several pairs of golden spots on the dorsum, while the belly is paler with occasional dark flecks.
In Illinois, there are just a handful of isolated populations of Desmognathus fuscus in Pulaski and Johnson counties. Although the overall conservation status of this species is that of least concern, in Illinois it is considered state endangered. Potential threats to populations include water pollution and urbanization.
Northern dusky salamanders are found in or near streams or springs. Important factors in their selection of suitable habitat include tree canopy cover, protective cover, and the size of the stream – these features can affect the density of salamanders within an area.
15) Northern zigzag salamander (Plethodon dorsalis)
- Native to the eastern United States
- Family: Plethodontidae
- Order: Urodela
- Conservation status: Least concern
The northern zigzag salamander ranges in length from 6.4 – 8.9 cm (2.3 – 3.5 in) and has 16 – 18 costal grooves. Females are generally slightly larger in size. The coloration of this salamander is dark brown, with a red or orange dorsal stripe that creates a zigzag pattern down the back. Individuals may also display red or orange skin near their axillae.
Plethodon dorsalis can be found in southern Illinois in Union, Johnson, Pope, Hardin, Alexander, Pulaski, and Massac counties. There is potentially an additional population in Vermilion, although this is not confirmed. This species is flexible in terms of habitat, occupying wooded hillsides, ravines, caves, and sinkholes, where it may be found under leaf litter or rocks.
Northern zigzag salamanders can detect chemical cues via their vomeronasal organ. Not only can they detect cues released by predators, but they are also sensitive to those from injured conspecifics – individuals will seek to avoid both.
