Pyrgulopsis amargosae


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Pyrgulopsis amargosae
Species Authority: Hershler, 1989
Common Name(s):
English Amargosa Springsnail
Pyrgulopsis micrococcus Hershler & Sada, 1987

Assessment Information [top]

Red List Category & Criteria: Vulnerable D2 ver 3.1
Year Published: 2011
Date Assessed: 2011-07-22
Assessor(s): Cordeiro, J. & Perez, K.
Reviewer(s): Böhm, M. & Collen, B.
Contributor(s): Dyer, E., Whitton, F., Soulsby, A.-M., McGuinness, S., De Silva, R., Kasthala, G., Milligan, H.T., Herdson, R., Thorley, J., McMillan, K. & Collins, A.
Pyrgulopsis amargosae has been assessed as Vulnerable under criterion D2 as it is found in five locations in a single drainage. Although its extent of occurrence is potentially up to 5,000 km², and there are no current declines or extreme fluctuations (i.e., it does not qualify under criterion B), it is likely to be impacted by future urban and agricultural development, particularly given the large scale developments occurring due to the rapid growth of Las Vegas and Los Angeles.

Geographic Range [top]

Range Description:This species is endemic to the lower Amargosa Basin in California (Hershler 1990). It occurs in five locations in a single drainage in Death Valley, although the extent of occurrence may be up to 5,000 km².
United States (California)
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population: There is no population information available for this species.
Population Trend: Unknown

Habitat and Ecology [top]

Habitat and Ecology: This species is found in springs along the lower Amargosa River (Hershler 1989).
Systems: Freshwater

Threats [top]

Major Threat(s): The Amargosa River is under threat from future development in California and Nevada, which would further affect the already dwindling water resources (e.g., aquifers) that feed the springs crucial to the survival of this species (Bureau of Land Management 2007). The rapid growth of Las Vegas and Los Angeles is already causing significant groundwater loss, destroying or altering habitat, introducing invasive species, and encouraging recreational activities along the Amargosa River (Nature Conservancy 2009).

Conservation Actions [top]

Conservation Actions: This species has a Global Heritage Status of G1 - Critically Imperilled (NatureServe 2009). The Amargosa River is designated as an Area of Critical Environmental Concern (ACEC), and sections of the river are included in other management plans (e.g., the National Wild and Scenic River System (NWSRS)) (BLM 2007). Further work is needed to ensure protection and management of populations of this species along the Amargosa River and population studies are recommended.

Bibliography [top]

Bureau of Land Management. 2007. Amargosa River: Area of critical environmental concern- implementation plan. United States Department of the Interior, Barstow, California.

Hershler, R. 1989. Springsnails (Gastropoda: Hydrobiidae) of owens and amargosa river (exclusive of ash meadows) drainages, death valley system, California-Nevada. Proceedings of the Biological Society of Washington 102(1): 176-248.

Hershler, R. 1990. Pyrgulopsis bruneauensis, a new springsnail (Gastropoda: Hydrobiidae) from the snake river plain, Southern idaho. Proceedings of the Biological Society of Washington 103(4): 803-814.

IUCN. 2011. IUCN Red List of Threatened Species (ver. 2011.2). Available at: (Accessed: 10 November 2011).

NatureServe. 2009. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. Internet

The Nature Conservancy. 2009. Hatchie River. Available at: (Accessed: 15th August).

Citation: Cordeiro, J. & Perez, K. 2011. Pyrgulopsis amargosae. In: The IUCN Red List of Threatened Species. Version 2015.2. <>. Downloaded on 03 September 2015.
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