Amphibians of North Carolina
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Plethodontidae Members:
NC Records

Plethodon cheoah - Cheoah Bald Salamander


Taxonomy
Class: Amphibia Order: Caudata Family: Plethodontidae Subfamily: Plethodontinae
Taxonomic Comments: The Plethodon jordani complex is a group of closely related forms that mostly are found at higher elevations in the southern Appalachian Mountains. Because they are largely restricted to mid to higher elevations and are absent from valleys, they form a series of geographic isolates that have diverged from one another to varying degrees. Depending on geographic location, the adults may be unmarked, or have red cheeks, red legs, or brassy frosting on their backs. Members of this group were traditionally treated as a single, geographically variable species known as Jordan's Salamander (Plethodon jordani). Hairston (1950) recognized seven subspecies of P. jordani, but Highton (1962) rejected these because some characters do not vary concordantly among the recognized taxa. In later papers, Highton (1970, 1972) recognized 12 geographic isolates in southern populations and argued that recognizing subspecies would serve no useful purpose.

Molecular studies (Highton and Peabody 2000, Weisrock and Larson 2006) have since revealed the presence of seven major evolutionary lineages that are now recognized as separate species (P. amplus, P. cheoah, P. jordani (sensu stricto), P. meridianus, P. metcalfi, P. montanus, and P. shermani). Some of the recognized species within the Plethodon jordani complex show both historical and current-day genetic influence from one or more other species, and mating studies indicate that none of these forms are completely reproductive isolated due to mating barriers (Reagan 1992, Wiens et al. 2006). Where adjoining forms come into contact, they generally tend to hybridize to varying degrees. In addition, certain members of this group also hybridize with members of the Plethodon glutinosus complex (Weisrock et al. 2005, Wiens et al. 2006). Discordance between mtDNA and nuclear data are well-documented (Weisrock and Larson 2006) and reflect various levels of gene-mixing. This not only is occurring today, but likely occurred historically during the Pleistocene as ranges expanded during glacial periods and previously isolated forms came into contact. Here, we recognize all of these species and discuss issues with hybridization in the individual species accounts.
Species Comments:
Identification
Description: The Cheoah Bald Salamander is a relatively large Plethodon that is dark gray to bluish black above with a grayish venter. The tail of adults is slightly longer than the body and is rounded in cross-section. The legs have orangish-red to reddish pigmentation on the dorsal surface that tends to be concentrated on the upper limbs. Some individuals may have very reduced reddish pigmentation, while others may have the entire dorsal surface covered with red. Sexually-active males have conspicuous, rounded mental glands. The adults vary from about 9-18 cm TL and there are usually 16 costal grooves.

This species is easily identified based on its red legs and restriction to the immediate vicinity of Cheoah Bald. Although it occurs microsympatrically with the Southern Appalachian Salamander (P. teyahalee), these species rarely hybridize (Highton and Peabody 2000). Plethodon cheoah is closely related to our other red-legged Plethodon, P. shermani. It is indistinguishable based on external morphology and patterning, but is genetically distinct (Weisrock et al. 2005).
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Observation Methods: Individuals are active at night outside of cover, but are otherwise found beneath logs, bark, stones and other cover on the forest floor.
AmphibiaWeb Account
Distribution in North Carolina
Distribution Comments: The Cheoah Bald Salamander is restricted to Cheoah Bald and vicinity in Graham County and Swain County in North Carolina. It has been found at elevational ranging from 975 m to near the top of Cheoah Bald at 1,524 m (Highton and Peabody 2000).
Distribution Reference: Highton and Peabody, 2000
County Map: Clicking on a county returns the records for the species in that county.
GBIF Global Distribution
Key Habitat Requirements
Habitat: Plethodon cheoah occurs on mesic slopes and in cove forests on Cheoah Bald. This species is fully terrestrial and lives in underground burrows and beneath cover objects on the forest floor. Populations reach their highest densities where there is a well-develop leaf litter layer, abundant rainfall, and lots of cover objects such as rotting logs and slabs of bark. Mature and old-growth stands provide optimal habitats.
Biotic Relationships: Interactions with other species are undocumented. This species occurs microsympatrically with the Southern Appalachian Salamander (P. teyahalee) over its entire elevational range and may potentially compete for cover or food resources.
See also Habitat Account for General Montane Mesic Forests
Life History and Autecology
Breeding and Courtship: Arnold (1976) observed courtship of members of the P. jordani complex from four geographic isolates and found them all to be indistinguishable. The following is a summary of the major aspects of breeding and courtship as summarized by Petranka (1998). These presumably apply to all seven recognized species in this complex.

Members of the P. jordani complex court from July through early October based on field observations. A female normally lays a clutch of eggs every other year, and only mates during the year when she nest. Arnold (1976) noted that males will not aggressively court sexually mature females that have small ovarian eggs, but will actively court females with large ovarian eggs.

When courting, a male approaches a female and begins nudging, nosing, or tapping her with his snout. He then places his mental gland and nasolabial grooves in contact with the back, sides, or tail of the female and engages in a 'foot dance' in which the limbs are raised and lowered off the substrate one at a time. The male eventually moves forward and presses his mental gland along the side of the female's head and over her nasolabial grooves. The male then turns his head under the female's chin and lifts. Next, the male circles under the female's chin and laterally undulates his tail as he passes. If the female is responsive, she places her chin on his tail and moves forward to the base of the tail. The pair then engages in a tail-straddle walk that may last for 1 hour. During the walk the male may turn and slap the female across her nasolabial region with his mental gland. This introduces pheromones via the nasolabial grooves.

The male eventually stops moving and begins a series of lateral rocking movements of his sacrum. The female begins a series of synchronous lateral head movements counter to the lateral movements of the sacral region of the male. The male then presses his vent to the substratum and deposits a spermatophore. Immediately after, he flexes the tail to one side and leads the female forward. She stops when her vent is over the spermatophore, then lowers her sacrum and picks up the sperm cap. During this process the male arches the sacral region and does a series of pushup motions with the rear limbs. The pair usually splits up and terminates courtship shortly after spermatophore deposition, even if the female is unsuccessful in picking up the spermatophore.
Reproductive Mode: The females are assumed to nest in underground cavities and burrows during the summer months, but the eggs have never been found.
Aquatic Life History: This is a fully terrestrial species that lacks a larval stage.
Terrestrial Life History: The juveniles and adults live on the forest floor and presumably feed on insects, millipedes, and other small prey like other members of the P. jordani complex (Petranka 1998). Almost all aspects of the life history of this species are undocumented, including diet, seasonal activity, growth and survival, age and size of sexually mature individuals, and longevity.
General Ecology
Population Ecology: Members of the P. jordani complex that inhabit mature forests have relatively stable populations that likely reflect density-dependent regulation associated with territoriality. The adults will aggressively defend their small territories from intruders, which likely sets an upper limit on population size. Territoriality and defense of space has yet to be studied in this species.
Community Ecology: Cheoah Bald Salamander shares forest-floor habitats with several other salamanders that have similar diets, but competitive interactions between these species has not been examined.
Adverse Environmental Impacts
Status in North Carolina
NHP State Rank: S1
Global Rank: G1G2
Status in North Carolina: SR
Environmental Threats: Climate change that results in hotter and drier conditions is the greatest threat to this species since it is isolated on a single mountain peak and cannot disperse to surrounding habitats via lower-elevation corridors.
Status Comments: Despite being a very narrow endemic, Plethodon cheoah is a relatively common species where it occurs locally on Cheaoh Bald. Extreme climate change could potentially results in the extinction of this species in the future.

Photo Gallery for Plethodon cheoah - Cheoah Bald Salamander

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Recorded by: Todd Pierson
Graham Co.