Home/Species/ Spring Mountains Pyrg

Pyrgulopsis deaconi

Hershler, 1998

Spring Mountains Pyrg

G1Critically Imperiled Found in 1 roadless area NatureServe Explorer →

G1Critically ImperiledGlobal Rank

MediumThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.118937

Element CodeIMGASJ0A70

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryInvertebrate Animal

Endemicendemic to a single state or province

KingdomAnimalia

PhylumMollusca

ClassGastropoda

OrderLittorinimorpha

FamilyHydrobiidae

GenusPyrgulopsis

Concept Reference

Hershler, R. 1998. A systematic review of the hydrobiid snails (Gastropoda: Rissooidea) of the Great Basin, western United States. Part I. Genus Pyrgulopsis. The Veliger, 41(1): 1-132.

Conservation Status

Rank MethodLegacy Rank calculation - Biotics v1

Review Date2019-12-05

Change Date1999-09-14

Edition Date2019-12-05

Edition AuthorsMiskow, E. NDNH

Threat ImpactMedium

Range Extent250-1000 square km (about 100-400 square miles)

Number of Occurrences6 - 20

Rank Reasons

Endemic to a few springs in the southern Spring Mountains in southern Nevada. Continued feral horse and burrow impacts, groundwater withdraw has extirpated one known population. Recreational use is persistent in the region and has degraded some spring systems. The Las Vegas and Pahrump valleys are under continual land development additionally, groundwater pumping for domestic wells are of concern for the persistence of the local aquifers and springs.

Range Extent Comments

This species is restricted to springs in the Spring Mountains in southern Nevada (Hershler 1998).

Occurrences Comments

Surveys in 2016 and other recent surveys (e.g., Pilgrim and Schwartz 2013, and USFS) document P. deaconi now occupying eight springs. All extant populations are on either BLM or USFS land, Manse Spring is on private land and the population is extirpated. Three of the surveyed springs were degraded by effects of feral horses and burros, two by diversion, and two by recreation. Restoration activities were observed at three springs.

Threat Impact Comments

Many of the spring sites where P. deaconi persist are impacted by feral horses and burros, nearby land development, groundwater withdraw/pumping as well as recreational activities have place undue stressors on spring systems. Restoration activities have enhanced some systems while others efforts have had negative effects on the spring system.

Ecology & Habitat

Other Nations (1)

United StatesN1

Province	Rank	Native
Nevada	S1	Yes

Threat Assessments

Threat	Scope	Severity	Timing
2 - Agriculture & aquaculture	Restricted (11-30%)	Moderate or 11-30% pop. decline	Unknown
2.3 - Livestock farming & ranching	Restricted (11-30%)	Moderate or 11-30% pop. decline	Unknown
2.3.1 - Nomadic grazing	Restricted (11-30%)	Moderate or 11-30% pop. decline	Unknown
6 - Human intrusions & disturbance	Small (1-10%)	Unknown	Unknown
12 - Other options	Unknown	Unknown	Unknown

Roadless Areas (1)

Nevada (1)

Area	Forest	Acres
Stirling - Clark B	Humboldt-Toiyabe National Forest	741

References (3)

Freshwater Mollusk Conservation Society (FMCS). 2021. The 2021 checklist of freshwater gastropods (Mollusca: Gastropods) of the United States and Canada. Considered and approved by the Gastropods Names Subcommittee December 2020. Online: https://molluskconservation.org/MServices_Names-Gastropods.html
Hershler, R. 1998. A systematic review of the hydrobiid snails (Gastropoda: Rissooidea) of the Great Basin, western United States. Part I. Genus <i>Pyrgulopsis</i>. The Veliger, 41(1): 1-132.
Sada, D. 2017. Environmental and Biological Factors Influencing Great Basin and Surrounding Areas Springsnail (Gastropoda:Rissooidea) Abundance and Distribution. Desert Research Institute. Report to U.S. Fish and Wildlife Service, Reno Fish and Wildlife Office, Southern Nevada Fish and Wildlife Office.

Pyrgulopsis deaconi

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