''Isthmura'' 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 ten ...

s in the family

Plethodontidae Plethodontidae, or lungless salamanders, are a family of salamanders. Most species are native to the Western Hemisphere, from British Columbia to Brazil, although a few species are found in Sardinia, Europe south of the Alps, and South Korea. In ...

. They are

endemic Endemism is the state of a species being found 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 found elsew ...

to Mexico. The genus, which corresponds to the former "''Pseudoeurycea bellii'' species group" and was first described as a

subgenus In biology, a subgenus (plural: 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 t ...

of ''

Pseudoeurycea ''Pseudoeurycea'' is a genus of salamander in the family Plethodontidae. The members of this genus are commonly known as the false brook salamanders. They are found in Mexico and Guatemala. In order to preserve ''Ixalotriton'' and ''Bolitoglossa ...

'', was raised to full generic level in 2015 in order to preserve '' Ixalotriton'' and ''

Bolitoglossa ''Bolitoglossa'' is a genus of lungless salamanders, also called mushroom-tongued salamanders, tropical climbing salamanders, or web-footed salamanders, in the family Plethodontidae. Their range is between northern Mexico through Central Americ ...

'' while avoiding

paraphyly In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

of ''Pseudoeurycea''.

Description

''Isthmura'' are large to very large salamanders, and the largest plethodontid salamanders in the

Neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...

. They have robust, black bodies that usually have bold red, orange, or pink markings. The toes have slight webbing. The fifth toe is well-developed. They inhabit montane forests mostly above , although ''

Isthmura gigantea ''Isthmura gigantea'', commonly known as the giant false brook salamander, is a species of salamander in the family Plethodontidae. It is endemic to Mexico and known from the eastern margins Sierra Madre Oriental between north-eastern Hidalgo and ...

'' and ''

Isthmura maxima The southern giant salamander (''Isthmura maxima'') is a species of salamander in the family Plethodontidae. It is endemic to Mexico and known from the Sierra Madre del Sur of western and southern Oaxaca and eastern Guerrero. It is the largest tr ...

'' have lower minimum altitude limits (respectively ).

Species

''Isthmura'' contains the following species:

References

{{Taxonbar, from=Q20939552 Amphibian genera Amphibians of North America Endemic amphibians of Mexico