Northern Redback Salamander

Plethodon cinereus

(Green 1818) - First named as a species by Green in 1818
in the Journal of the Academy of Natural Sciences,
Philadelphia. (1) 1:356.

Redback phase	Leadback phase

Description: Plethodon cinereus has a long, slender body that is slightly flattened dorsally and well-rounded on the sides. There are ususally 18-19 costal grooves but the number can vary from 17-20. Redback salamanders have a prominent gular fold. They have small legs with short, thick toes. The five hind toes are slightly webbed at the base. There are 4 toes on the forefeet. Their tongue does not fill the floor of their mouth. The vomerine teeth form two backward-curving lines of 5-7 teeth that are separated from each other and from the parasphenoid teeth. P. cinereus can occur in 2 distinct color phases, the redback phase and the leadback phase. The redback phase is characterized by a broad, median, dorsal band that extends from the head through the trunk and down the tail. The color of the stripe can vary from light grey and dull yellow to bright red. Some stripes may even contain specks of black. The sides of the body are dark grey or black and become lighter towards the belly. The belly is mottled grey and white. In the leadback phase the body is uniformly dark grey to black with the head and legs a little lighter. In some localities both phases are equally represented, in other localities one phase may predominate.

Sexual Differences: The male tends to have a more swollen snout, enlarged premaxillary teeth, and proportionally longer legs. Males also tend to be smaller than females in body length.

Range: West to Missouri, north to Quebec, south to South Carolina

Habitat: P. cinereus is completely terrestrial. Redback salamanders can usually be found under logs, moss, stones, and other debris on the floor of a deciduous, evergreen, or mixed forest. They are most abundant in areas with a lot of moisture.

Feeding: P. cinereus feeds on a wide variety of invertebrates. The type of inverebrate depends on the environment. Such invertebrates include flies, spiders, snails, earthworms, ants, and a variety of other insects. Prey is captured by quickly thrusting their tongue forward. P. cinereus is limited to forage in moist areas and so are able to forage optimally shortly after rainfall. However, during dry periods when P. cinereus is restricted to under rock and logs, foraging becomes tougher. Therefore, P.cinereus will gourge itself during favorable foraging conditions and live off its fat reserves when food becomes scarce.

Reproduction: Mating season runs from October until December. Courtship consists of the male rubbing a substance from a gland on his chin onto the head and nose of the female to stimulate her to breed. Eventually, the male deposits spermatophores which are later recovered by the female in her cloaca. The female will lay her eggs between June and July in the North. Eggs are usually deposited in clusters of 8-10, but can vary between 3-13. These clusters are held together and suspended from the ceiling of the salamander's nest, usually a rotted out log but may also be any avaliable crack or crevice. The female will tend the eggs until they hatch. P. cinereus is entirely terrestrial. There is no aquatic larval stage. Broad, flat gills reach full development before the larva hatches from its egg envelope but will only persist a few days after hatching. In the redbacked phase, the dorsal band is well developed by the time of hatching. Sexual maturity occurs after about 2 years.

Specimens: avaliable at The Peabody Museum of Natural History at Yale University

Conservation: Although P. cinereus is common throughout much of Eastern North America, future population problems may occur due to human pollution.

Web page compiled by Kathy Ching