Northern Slimy Salamander

Plethodon glutinosus (Green 1818)

northern slimy salamander
Northern Slimy Salamander, St. Clair County, Illinois.

Key Characters: White or silvery dots and flecks scattered over the body, commonly concentrated along lower sides; nasolabial grooves present.

Similar Species: Blue-spotted Salamander, Jefferson Salamander, Silvery Salamander, and Small-mouthed Salamander are similar overall, but these species lack nasolabial grooves. See Key to Adult and Larval Salamanders of Illinois for help with identification.

Subspecies: No subspecies currently recognized.

juvenile slimy salamander
juvenile slimy salamander, Wayne County, Illinois. photo by C.A. Phillips

Description: Medium-sized (up to 17 cm TL) salamander with black or bluish black back and uniform gray-black belly, sometimes with light flecks. Costal grooves 14-15. Tail long and circular in cross-section. Head relatively large. Adult male with a light circular hedonic gland under chin. Recently hatched juvenile may have short, white gills.

Habitat: Eastern deciduous forests under bark or other debris on ground, especially on hillsides.

Natural History: This completely terrestrial salamander can be found in burrows, under rocks, in and under logs, and in rotten tree stumps in spring and autumn, but disappears deeper into soil during summer and winter. It prowls the forest floor at night feeding on worms and arthropods. Copious, adhesive skin secretions provide protection from predators. Tiny hatchlings, which resemble adults in form and color, grow to become the largest completely terrestrial salamanders in Illinois. Females deposit and brood clusters of 10-20 large white eggs in damp rotten logs, burrows, or rock crevices. Brooding females were observed in rock crevices in a southern Illinois cave during October and November. The embryos hatched by May of the following year.

Distribution Notes: Roughly the southern half of Illinois. A record from “Abingdon, Knox County, IL” collected by Garman (no date); CAS-SUA 597, is doubtful as this is well north and west of the NW limits of the species range.

Status: Most commonly encountered woodland salamander in southern half of state.

EtymologyPlethodon – pletho (Greek) for crowd, multitude, fullness; odon (Greek) tooth; glutinosus – (Latin) viscous, sticky

Original Description: Green, J. 1818. Descriptions of several species of North American Amphibia, accompanied with observations. Journal of the Academy of Natural Sciences Philadelphia. 1(1):348-359.

Type Specimen: Not designated.

Type Locality: Not stated. Restricted to Princeton, New Jersey by Dunn (1926, Salamanders of the Family Plethodontidae:138).

Original Name: Salamandra glutinosa Green, 1818

Nomenclatural History: Transferred to Plethodon and emmended to glutinosus by Tschudi (1838, Classif. Batr.: 92).  Emended to Plethodon glutinosum by Gray (1850, Cat. Spec. Amph. Coll. Brit. Mus., Batr. Grad.: 39). Transferred to Cylindrosoma by Duméril, Bibron, and Duméril (1854, Erp. Gén., 9: 80).  First use of trinomial by Dunn (1920, Proc. Biol. Soc. Washington, 33: 131).  Most subspecies elevated to species by Highton et al., (1989,  Illinois Biological Monographs 57: 1-153).