Plethodon glutinosus is now taxonomically defined as a genetic complex consisting of at least thirteen species discernible only through laboratory testing, though many species are indistinguishable in the field and are therefore still considered for this project to be subspecies of a single lineage (Highton et al. 1989).
According to the U.S. Fisheries and Wildlife Service, the slimy salamander is considered neither a threatened nor endangered species throughout its range. However, some species within the P. glutinosus complex (see Other Comments) may be candidates for the endangered and threatened species lists (USFWS 1999).
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Development - Life Cycle: metamorphosis
Prey of P. glutinosus consists mainly of ants (42%), followed by beetles (26%), sowbugs, and earthworms, depending on what is seasonally most prevalent (Davidson 1956).
The slimy salamander has an extensive range throughout the eastern and central United States. Starting in central New York and the southern tip of Wisconsin, the range covers much of the eastern seaboard, moving southward to central Florida and the Gulf coast and westward to parts of east Texas and Oklahoma. It is notably absent from the lower Mississippi valley, presumably because flooding causes frequent disturbance to the preferred habitat of the slimy salamander in that region (Grobman 1944).
Biogeographic Regions: nearctic (Native )
The slimy salamander is commonly found beneath stones and decaying logs in wooded areas and alongside streams, as well as in the crevices of shale banks and along the sides of gullies and ravines (Davidson 1956; Grobman 1944). It generally moves about underground using animal and insect burrows (Cowley 1999). Mean home-range area is 3.01 +/- .613 sq. meters for adults and 3.46 +/- 1.851 sq. meters for juveniles (Marvin 1998).
Terrestrial Biomes: forest
Average lifespan
Status: captivity: 5.5 years.
The slimy salamander has mainly black skin, covered by abundant silver-white or brassy specks, or both; the ventrum has variable shades but is generally lighter than the dorsum. The organism is distinguished from other dark salamanders in its range by the presence of a nasolabial groove. More noticeably, P. glutinosus is defined by a slimy, glue-like secretion released from its skin glands. It has 16 costal grooves, on rare occurrences 15 or 17, and generally ranges from 4.75 to 6.75 inches in length (Conant and Collins 1998). Hatchlings are born with only slight dark coloration on the dorsum and none on the ventrum; melanin for the specks begins to appear on the dorsum after three days. Adult females exhibit slightly larger snout-to-vent lengths than adult males, but are otherwise similar in appearance (Highton 1956).
Other Physical Features: ectothermic ; bilateral symmetry
Average mass: 4.2 g.
Average basal metabolic rate: 0.00191 W.
Breeding of P. glutinosus takes place at the beginning of April and eggs are deposited anytime from late spring in the northern part of the range to very late summer at the range's southern tip. Eggs are laid in moist areas such as caves or under the bark of rotting trees. Clutch size ranges from 4 to 12 eggs. Hatchlings emerge close to three months after eggs are deposited (Highton 1956). Juveniles have no aquatic stage and develop directly to adulthood, as the species is entirely terrestrial (Feder 1983).
Female slimy salamanders do not sexually mature until they are two years old, and cannot lay eggs until approaching age three. The same is true for most males, although some have been found capable of breeding at two years of age. In regions where the growing season is short, a wait of three years is almost certain before sexual maturity is reached (Highton 1962).
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate)
Average number of offspring: 21.
Average age at sexual or reproductive maturity (male)
Sex: male: 910 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 910 days.
The northern slimy salamander (Plethodon glutinosus) is a species of terrestrial plethodontid salamander found throughout much of the eastern two-thirds of the United States.
The northern slimy salamander is called "slimy" because it produces sticky slime from glands on its lower back and tail in order to defend itself from predators.[2] It is also sometimes referred to as the viscid salamander, grey-spotted salamander, slippery salamander, or sticky salamander, depending on which source is consulted.[3]
The northern slimy salamander is typically an overall black in color, with numerous silvery spots or gold spots across its back. It is usually 12–17 cm (4.7–6.7 in) in total length (including tail), but can grow to 20.6 cm (8.1 in).[4] Males are not easily distinguished from females, though females tend to be slightly larger. It has 15-17 costal grooves.
P. glutinosus is one of 57 species in the genus Plethodon and was one of the first of its cogeners to be described. The Northern Slimy Salamander is one of 14 species within the Plethodon glutinosus complex. Species within this complex are very similar but vary in habitat range, body size, shape, and proportions.[5]
P. glutinosus is found from New York, west to Illinois, south to Mississippi, and east to Alabama, with isolated populations in southern New Hampshire and northwestern Connecticut.[6]
P. glutinosus is highly associated with moist undisturbed woodlands, and ravines. The salamander is typically located on the underside of debris such as logs and stones during the day. P. glutinosus will emerge from debris on moist nights.[7] They can be found in areas of secondary succession in old growth deciduous or hemlock forests with steep, rocky slopes.[8] They prefer hiding under rotten logs and in decomposed organic matter like layers of duff on the forest floor. They can typically be found near a water source or in a moist areas. The clear-cutting of forests greatly reduces population numbers in the given area, where it takes 13 years for the population to return to half of what it was before the clear-cutting.[9]
All plethodontid salamanders are territorial, and fight aggressively for territory. Their preferred habitat is in moist soil or leaf litter beneath stones, rotting logs, or other debris near a permanent water source. They sometimes make use of other animals' burrows. Their diet consists primarily of ants, beetles, sow bugs, and earthworms, but they will consume most kinds of insect. As their name suggests, slimy salamanders produce significant amounts of skin secretions that are highly adhesive. These adhesives bind to predators and can compromise both mastication and locomotion.[10]Whenever threatened they will thrash their tail, exposing the glands that secrete this sticky substance.[11]
Females reach sexual maturity in the second year of life and do not lay eggs until the third year.[12] Breeding of P. glutinosus takes place in the spring and is terrestrial. Courtship consists of the males performing a sort of dance to attract the females' attention. Females lay clutches of four to 12 eggs in a moist area, which she guards, often neglecting food for the period until they hatch. Hatchlings emerge from the eggs in about three months, having no aquatic stage, like many other salamander species. They instead develop directly into their entirely terrestrial adult form. After hatching, young individuals show high growth rates during the summer months and little to no growth during the winter.[13]
Not much is known about the diet of the slimy salamanders, but it is believed that the species exhibit opportunistic feeding strategies where they consume prey that is easily accessible. One study surveyed the digestive systems of this species and found that ants, bees, wasps, beetles, sowbugs, snails, and earthworms occurred most frequently.[14][15]
The northern slimy salamander (Plethodon glutinosus) is a species of terrestrial plethodontid salamander found throughout much of the eastern two-thirds of the United States.
