''Plethodon'' is a genus of

salamander Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All t ...

s in the family

Plethodontidae Plethodontidae, or lungless salamanders, are a family of salamanders. With over 500 species, lungless salamanders are by far the largest family of salamanders in terms of their diversity. Most species are native to the Western Hemisphere, from B ...

. They are commonly known as woodland salamanders. All members of the genus are

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to North America (Canada and the United States). They have no aquatic larval stage. In some species, such as the

red-backed salamander The red-backed salamander (''Plethodon cinereus'') is a small, hardy woodland salamander species in the Family (biology), family Plethodontidae. It is also known as the redback salamander, eastern red-backed salamander,Integrated Taxonomic Inform ...

(''

Plethodon cinereus The red-backed salamander (''Plethodon cinereus'') is a small, hardy woodland salamander species in the family Plethodontidae. It is also known as the redback salamander, eastern red-backed salamander,Integrated Taxonomic Information System nte ...

''). Young hatch in the adult form. Members of ''Plethodon'' primarily eat small invertebrates. The earliest known fossils of this genus are from the

Hemphillian The Hemphillian North American Stage on the geologic timescale is a North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 10,300,000 to 4,900,000 years BP. It is usually considered t ...

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

in the United States.

Taxonomy

''Plethodon'' is part of the family Plethodontidae (lungless salamanders) and the subfamily

Plethodontinae Plethodontidae, or lungless salamanders, are a family of salamanders. With over 500 species, lungless salamanders are by far the largest family of salamanders in terms of their diversity. Most species are native to the Western Hemisphere, from B ...

. The genus ''Plethodon'' can be divided into two

subgenera In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

: the nominal subgenus ''Plethodon'', which includes up to 49 eastern species (the bulk of diversity in the genus), and the subgenus ''Hightonia'', which includes 9 species native to the western part of North America. The eastern ''Plethodon'' subgenus can be further categorized into at least three major

species groups In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

which genetic analyses confirm to be

clades In biology, a clade (), also known as a monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy ...

: * The ''Plethodon cinereus'' group, which contains the ubiquitous red-backed salamander and 9 other small, slender species ('' P. electromorphus, P. hoffmani, P. hubrichti, P. nettingi, P. richmondi, P. serratus, P. shenandoah, P. sherando,'' and '' P. virginia''). * The ''Plethodon wehrlei'' group is a species complex centered on Wehrle's salamander and at least 4 of its close relatives ('' P. dixi'', '' P. jacksoni'', '' P. pauleyi'', '' P. punctatus''). Some of these species were only formally distinguished from ''P. wehrlei'' as recently as 2019. * The ''Plethodon welleri'' group includes Weller's salamander and the three species of zigzag salamander ('' P. angusticlavius, P. dorsalis, P. ventralis'')''.'' Many studies have argued that the ''wehrlei'' and ''welleri'' groups should be conceived of as one larger clade, the ''Plethodon wehrlei-welleri'' group. * The ''Plethodon glutinosus'' group is the largest species group within ''Plethodon'', with around 30 species and several subordinate species complexes. Many species within this group (including the nominal species) are commonly known as "slimy salamanders", characterized by a large size, robust build and black-and-white coloration. Not all members of the ''Plethodon glutinosus'' group are labelled as slimy salamanders, and

species delimitation A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of classification and a ...

among slimy salamanders and their close relatives is a subject of continued debate. For example, some studies interpret ''Plethodon grobmani'' and ''Plethodon mississippi'' to be

junior synonyms In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The botanical and zoological codes of nomenclature treat the concept of synonymy differently. ...

of ''Plethodon glutinosus'', based on a lack of genetic or anatomical distinctiveness. * One difficult-to-classify species is Webster's salamander, which may lie among the ''wehrlei-welleri'' group or the ''glutinosus'' group, or outside both groups, depending on the study.

List of species

As of 2024 there are up to 58 species in the genus ''Plethodon''. Most are native to eastern and central North America, with the

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, are a mountain range in eastern to northeastern North America. The term "Appalachian" refers to several different regions associated with the mountain range, and its surrounding terrain ...

having the highest diversity. Seven species live along the West Coast, one (''P. idahoensis'') in the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...

Idaho Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...

, and one (''P. neomexicanus'') in the

Jemez Mountains The Jemez Mountains (, Tewa: ''Tsąmpiye'ip'įn'', Navajo: ''Dził Łizhinii'') are a group of mountains in Rio Arriba, Sandoval, and Los Alamos counties, New Mexico, United States. Numerous Puebloan Indian tribes have lived in the Jemez Moun ...

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

. All 58 ''Plethodon'' species listed in alphabetical order of

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

: ''

Nota bene ( ; plural: ) is the Latin language, Latin phrase meaning ''note well''. In manuscripts, ''nota bene'' is abbreviated in upper-case as NB and N.B., and in lower-case as n.b. and nb; the editorial usages of ''nota bene'' and ''notate bene'' fi ...

'': A

binomial authority In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

in parentheses indicates that the species was originally described in a genus other than ''Plethodon''.

Intrinsic Phylogeny

Intrinsic phylogeny tree of genus ''Plethodon''.

References

{{Taxonbar, from=Q2256290 Amphibian genera Taxa named by Johann Jakob von Tschudi