Eurycea nana


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Eurycea nana
Species Authority: Bishop, 1941
Common Name(s):
English San Marcos Salamander

Assessment Information [top]

Red List Category & Criteria: Vulnerable D2 ver 3.1
Year Published: 2004
Date Assessed: 2004-04-30
Assessor(s): Geoffrey Hammerson, Paul Chippindale
Reviewer(s): Global Amphibian Assessment Coordinating Team (Simon Stuart, Janice Chanson, Neil Cox and Bruce Young)
Listed as Vulnerable because it is known from only a single location.
1996 Vulnerable (Baillie and Groombridge 1996)
1996 Vulnerable
1994 Rare (Groombridge 1994)
1990 Rare (IUCN 1990)
1988 Rare (IUCN Conservation Monitoring Centre 1988)
1986 Rare (IUCN Conservation Monitoring Centre 1986)

Geographic Range [top]

Range Description: This species is known only from a pool at the source of the San Marcos River (San Marcos Springs, Spring Lake), Hays County, Texas, United States, and a short distance downstream (Chippindale et al. 2000). A second, smaller population of this species was thought to occur in the Comal River (Springs), slightly to the west in Comal County; however, this population recently was determined not to be E. nana (Chippindale, Hillis and Price 1994, Chippindale, Price and Hillis 1998, Chippindale et al. 2000).
United States
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: It is abundant within its limited range, where the population is stable. Population densities were estimated to be about 116-129 individuals per m² in vegetation mats (Tupa and Davis 1976; Nelson 1993). The entire population has been estimated as about 53,200 individuals in vegetation mats and suitable rocky substrates (USFWS 1996).
Population Trend: Stable

Habitat and Ecology [top]

Habitat and Ecology: It can be found in shallow alkaline springs carved out of limestone. They have been found in mats of blue-green algae (Lyngbya sp.), under rocks, and in gravel substrate at water depths of less than 1m to several metres. The species is completely aquatic and does not metamorphose. Eggs have never been observed in the wild. In captivity, ovipositioning has occurred on aquatic moss, filamentous algae, rocks, and glass marbles.
Systems: Freshwater

Threats [top]

Major Threat(s): It is vulnerable to alterations in water level and water quality that may result from agricultural and residential development.

Conservation Actions [top]

Conservation Actions: Its range is protected at both the state and federal level. It is listed as Threatened by the state of Texas and Threatened by the Federal government. There is a need for close monitoring of the population status of this species.

Citation: Geoffrey Hammerson, Paul Chippindale 2004. Eurycea nana. The IUCN Red List of Threatened Species. Version 2014.3. <>. Downloaded on 26 March 2015.
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