Plethodon cylindraceus
White-spotted Slimy Salamander

Plethodon cylindraceus occurs in the southern Appalachian and piedmont regions of the Appalachian Highlands, as well as the southern coastal plain. It is found in the Blue Ridge and Piedmont physiographic provinces of Virginia and North Carolina, west to the French Broad River and south to the Northern Piedmont of South Carolina. Outside of that area, P. cylindraceus can also be found in the Valley and Ridge Physiographic province in western Virginia and eastern West Virginia, as well as in a small area of the Coastal Plain Physiographic province of eastern Virginia. (Beamer and Lannoo, 2010; Duellman, 1999)

Plethodon cylindraceus lives in terrestrial oak-hickory forests with a significant layer of leaf litter. Typically, both juveniles and adults are found under logs and other cover objects; they are rarely found in the leaf litter. Most specimens have been found near water sources, and they are active on moist forest floors during the night from spring to fall. During dry periods, P. cylindraceus gather in moist areas under cover objects or move underground. Seasonally, P. cylindraceus will move underground during winter months. They are found at high elevations, averaging 1676 meters above sea level. (Beamer and Lannoo, 2010; "white-spotted slimy salamander (Plethodon cylindraceus)", 2010; "Northern Slimy Salamander", 2007)

Plethodon cylindraceus, like most salamanders, feature slender bodies, short noses, and long tails. Most individuals have large dorsal and lateral white spots. Adults may reach 11.4 to 20.6 cm in length. This species is typically shiny black with a dark throat and slate belly color. Plethodon cylindraceus also has 15 to 17 costal grooves. Its limbs are set at right angles to the trunk, and the forelimbs and hind limbs are of equal size, typical of most salamanders in general. (Bruce, et al., 2000; Hickman Jr., et al., 2009; "Northern Slimy Salamander", 2007)

Little is known regarding the development of this species. Females lay eggs in moist, terrestrial burrows or crevasses in late spring or early summer. All development occurs within the eggs, thus there is no aquatic larval stage. The young emerge 2 to 3 months later as sub-adults. Juveniles measure around 20 mm in length at one year of age and are oftentimes found under logs. Juveniles become reproductively mature at 4 to 5 years old, at which time they measure 50 to 76 cm snout-vent length (SVL). (Beamer and Lannoo, 2010)

During the spring, male Plethodon cylindraceus search for female mates typically underneath logs. Once a male finds a female mate, he places his nasolabial grooves and mental glands against the female’s body. The male displays a foot dance in which he raises and lowers his rear limbs simultaneously or alternately. The male then moves towards the female’s head while repeatedly rubbing his nasolabial grooves on the female. Once the male reaches the female's head he rubs his mental gland over her head and nasolabial grooves. The male then places his head under her chin and attempts to pass beneath her, waving his tail as it passes under the female’s mouth. When the male stops moving forward, the female grabs on to his tail and then the pair move forward while the female is grasping onto the male. The pair continues to move forward until the spermatophore is deposited. No mate defense has been observed for this species. (Beamer and Lannoo, 2010)

Plethodon cylindraceus begins courtship and mating in the spring and fall. White spotted slimy salamanders lay six to thirty six eggs in an underground retreat such as underneath or within a log, or in a moist crevasse during late spring. The female is tasked with guarding the nest and her eggs hatch after 2 to 3 months. Plethodon cylindraceus displays no aquatic larval stage. The larvae hatch in late summer and take 4 to 5 years to mature. Females lay eggs typically once every other year. ("Northern Slimy Salamander", 2007)

Plethodon cylindraceus females that are breeding go underground to brood their eggs for 2 to 3 months until they hatch. Male involvement has not been documented after initial mating. (Beamer and Lannoo, 2010; "Plethodon glutinosus (Green), Northern slimy salamander - Biodiversity of Great Smoky Mountains National Park", 2010)

Plethodon cylindraceus is typically long-lived and can live for five to ten years. ("Plethodon glutinosus (Green), Northern slimy salamander - Biodiversity of Great Smoky Mountains National Park", 2010)

Plethodon cylindraceus is a terrestrial species and completes its entire life cycle on land. It is also a lungless species and breaths through its skin and membranes of the mouth and throat. White-spotted slimy salamanders are named for their spotted appearance and defensive strategy of secreting a very sticky substance from its skin glands that is extremely difficult to remove.

White-spotted slimy salamanders are generally solitary, but will congregate under optimal cover objects to avoid dessication during dry periods. Females and juveniles are much more likely to share a cover object than multiple, territorial males.

White-spotted slimy salamanders may be active during the day or night, but are most active during rain events and at night. Little is known regarding migratory movements, but studies have shown that individuals move no more than 90 meters. Distance moved seems to correlate with age and more specifically, reproductive maturity. Juveniles move less than 6 m, whereas salamanders between 55 and 65 SVL moved the most. This length is most seen in individuals that have recently reached reproductive maturity and are likely moving in search of mates. (Beamer and Lannoo, 2010; "Northern Slimy Salamander", 2007)

Territory size is not well documented in this species, but males rarely will occupy the same cover object. The maximum recorded distance traveled for an individual is 91.5 m, but most adults do not move more than 9 m.

In order to perceive the environment, Plethodon cylindraceus uses its cornea as its principle refractive surface for bending light in air. Plethodon cylindraceus has eyelids and lachrymal glands to protect and wash its eyes. This species ear contains a tympanic membrane, or eardrum, and stapes that are used to transmit vibrations to its inner ear. It uses vision, olfaction, vibration sense, mechanoreception, and electroreception to communicate with others and perceive the environment. When mating, males incorporate a "dance" to attract females. Males also produce hormones that are rubbed onto the female during mating rituals. (Beamer and Lannoo, 2010; Hickman Jr., et al., 2009; Roth, 1987)

Plethodon cylindraceus, like all salamanders, are capable of eating a myriad of prey ranging in size and species, completely ingesting whatever prey they encounter with the exception of the size constraints of their mouths. What P. cylindraceus eats is largely determined by the amount of prey within its habitat and the time of year. Salamanders are carnivorous, eating animal food both before and after metamorphosis. Plethodon cylindraceus consumes leaf litter invertebrates including spiders, beetles, ants, millipedes, slugs, worms and insect larvae. (Roth, 1987; "white-spotted slimy salamander (Plethodon cylindraceus)", 2010)

Two North American snakes are known predators of Plethodon cylindraceus. Garter snakes (Thamnophis genus) and copperheads (Agkistrodon contortrix) feed on white-spotted slimy salamanders. All species of the Plethodon genus produce noxious skin secretions as predator defense. White-spotted slimy salamanders produce copious amounts of slime which often gum up a predator's mouth, giving the salamander a chance to escape. Plethodon cylindraceus become immobile when physically contacted, making them less likely to become detected by visually oriented predators. (Beamer and Lannoo, 2010)

Plethodon cylindraceus impact their communities with their burrowing by contributing to the dynamics of the soil. They dig and break up the soil to increase aeration. White-spotted slimy salamanders also are host to many internal parasites including: Cryptobia borreli, Eutrichomastix batrachorum, Haptophyra gigantean, Haptophyra michiganensis, Hexamastix batrachorum, Hexamitus intestinalis, Karotomorpha swezi, Prowazekella longifilis, Tririchomonas augusta, Brachycoelium hospitae, Capillaria inequalis, Cosmocercoides dukae, Oswaldocruzia pipiens, Oxyuris magnavulvaris, Acanthocephalus acutulus, and Hannemania dunni. (Hairston, 1987)

There are no positive effects of Plethodon cylindraceus on humans. (Beamer and Lannoo, 2010)

There are no adverse effects of Plethodon cylindraceus on humans. (Beamer and Lannoo, 2010)

Plethodon cylindraceus is not protected by any state and is labeled as least concern by the IUCN Red List. IUCN Red List states that this species has a wide distribution and a large population, and thus is not threatened at this time. This species is abundant within its range and is tolerant to habitat alteration. Selective timber harvesting has not shown any negative effects on P. cylindraceus, but clearcuts may cause local population declines. (Beamer and Lannoo, 2010)