The limestone salamander (''Hydromantes brunus'') is a member of the

lungless salamander 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 ...

family. Discovered in 1952, this species belongs to a genus

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 els ...

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

. It is endemic to a portion of the

Merced River The Merced River (), in the central part of the U.S. state of California, is a -long tributary of the San Joaquin River flowing from the Sierra Nevada into the San Joaquin Valley. It is most well known for its swift and steep course through the ...

Canyon in

Mariposa County, California Mariposa County () is a county in the U.S. state of California. As of the 2020 U.S. Census, the population was 17,131. The county seat is Mariposa. It is located in the western foothills of the Sierra Nevada mountains, north of Fresno, eas ...

Description

The limestone salamander has a flattened body, head, webbed toes, and a short tail. It is typically 5.0-7.5 cm in length. Adults are brownish with a pale ventral surface; the male has oval-shaped mental gland. The species was originally thought to be life-birthing, but is now known to lay eggs. Young hatch in the egg and emerge fully formed, with no larval stage. They are yellowish greenish, darkening with age. Like all lungless salamanders, it respires through its skin.

Distribution and habitat

The genus ''

Hydromantes ''Hydromantes'', commonly referred to as web-toed salamanders, is a genus of the lungless salamander family, Plethodontidae; they achieve respiration through their skin and the tissues lining their mouth. They are endemic to mountains of Californ ...

'' is

to California. The limestone salamander occurs only in the

Lower Merced River The Merced River (), in the central part of the U.S. state of California, is a -long tributary of the San Joaquin River flowing from the Sierra Nevada into the San Joaquin Valley. It is most well known for its swift and steep course through the ...

drainage, in several disparate localities, at elevations of 300–760 m in inhabits canyon slopes that are greater than 35 degrees. Habitats include moss-covered limestones outcroppings, chaparral, under rocks and logs in moist environments. During dry weather it stays underground in caves and rock crevices.

Conservation

The limestone salamander is classified as near threatened by the IUCN, mostly because it is known from fewer than five locations (where the species appears to be uncommon but not rare). Under the Department of the Interior, US Fish and Wildlife, its Federal listing status is currently under review. The species is listed as Threatened by the California Department of Fish and Wildlife under the State Endangered Species Act. A proposed gold operation mine in Hell Hollow is thought to be the most immediate threat, in addition to general habitat loss due to construction of highways, quarries and dams. A portion of the Merced River Canyon is protected by the State of California and managed by the State Department of Fish and Wildlife as the Limestone Salamander Ecological Reserve (~120 acres); a further 1,600 acres have been designated as the Limestone Salamander Area of Critical Environmental Concern.

References

{{Taxonbar, from=Q308239 Hydromantes Amphibians of the United States Endemic fauna of California Fauna of the Sierra Nevada (United States) Merced River Natural history of Mariposa County, California Taxonomy articles created by Polbot Amphibians described in 1954