Home/Species/ Southeast Nevada Pyrg

Pyrgulopsis turbatrix

Hershler, 1998

Southeast Nevada Pyrg

G3Vulnerable Found in 1 roadless area NatureServe Explorer →

G3VulnerableGlobal Rank

MediumThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.982242

Element CodeIMGASJ0H80

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryInvertebrate Animal

Endemicendemic to a single nation

KingdomAnimalia

PhylumMollusca

ClassGastropoda

OrderLittorinimorpha

FamilyHydrobiidae

GenusPyrgulopsis

Other Common Names

southwest Nevada pyrg (EN)

Concept Reference

Hershler, R., H.-P. Liu and C. Bradford. 2013. Systematics of a widely distributed western North American springsnail, Pyrgulopsis micrococcus (Caenogastropoda, Hydrobiidae), with descriptions of three new congeners. ZooKeys 330:27-52.

Taxonomic Comments

The southwest Nevada pyrg, Pyrgulopsis turbatrix was previously confused with P. micrococcus, which also occurs in southern Nevada but differs in its more elongate shell, narrower, usually longitudinal (not transverse) terminal gland on the penis, and frequent presence of the penal gland. The taxonomic revision (Hershler et al. 2013) expanded the range of the southwest Nevada Pyrg into California when some populations of the Oasis Valley pyrg were reassigned as the southwest Nevada pyrg based on molecular phylogenetic analysis and morphology.

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2021-08-29

Change Date2021-08-29

Edition Date2021-08-29

Edition AuthorsMiskow, E. NDNH

Threat ImpactMedium

Range Extent20,000-200,000 square km (about 8000-80,000 square miles)

Number of Occurrences21 - 80

Rank Reasons

This species is known from fairly restricted geographical area where some land protections are in place but some occurrences have nonetheless become extirpated. The species is also subject to threats from water diversions, livestock, and recreational activities.

Range Extent Comments

This species is found in springs and spring provinces in southern Nevada and southern California, USA (Hershler et at. 2013). The specific areas where the species in known to occur are: the northwest and northeast flanks of the Spring Mountains in Clark and Nye counties, Nevada; in Death, Panamint, and Saline Valleys, and in the San Bernardino Mountains in San Bernardino and Inyo counties, California.

Occurrences Comments

This species is known from 34 historical occurrences. A 2016 survey of most of the Nevada populations and a portion of the California populations recorded 17 occurrences persisting.

Threat Impact Comments

Threats to this species include water diversions, livestock grazing, and recreational activities. Vegetation and soil disturbance from ungulates (feral horses and burro's) and hikers occurs as several spring systems within the species range. Several springs have surface water manipulations to them in the form of piping and channel modifications at all or portions of the flow for agricultural and or livestock usage, diminishing this species habitat.

Ecology & Habitat

Habitat

Microhabitat preference observations found P. turbatrix was most abundant near the spring source and its abundance steadily decreased downstream as is typical of the genus Pyrgulopsis. Water temperature preferences were from approximately 18 deg C to 1 deg C and avoids temperatures greater than 20 deg C. Depths of the southwest Nevada pyrg were generally in shallow (~ 1 cm), slow moving habitat (~1 cm/sec), avoids habitat that is swift (more than 4 cm/sec), and it was scarce or absent from shallow habitats without flowing water.

Ecology

Knowledge of P. turbatrix ecology comes from work in Grapevine Spring (Sada and Mihevc 2011). Habitat preferences were found to be slightly and moderately disturbed by ungulates (horses and burros) (there was no habitat that was unaffected by this disturbance at Grapevine Spring), and avoided habitat that was highly disturbed by ungulates. There was no preference for either the type of substrate or aquatic vegetation, however it was most abundant in fine substrate and where there was watercress (Rorippa officinale). This taxon did not occupy impounded, ponded habitat.

Other Nations (1)

United StatesNNR

Province	Rank	Native
Nevada	S1	Yes
California	SNR	Yes

Threat Assessments

Threat	Scope	Severity	Timing
2 - Agriculture & aquaculture	Restricted (11-30%)	Moderate or 11-30% pop. decline	High (continuing)
2.3 - Livestock farming & ranching	Restricted (11-30%)	Moderate or 11-30% pop. decline	High (continuing)
2.3.1 - Nomadic grazing	Restricted (11-30%)	Moderate or 11-30% pop. decline	High (continuing)
6 - Human intrusions & disturbance	Restricted (11-30%)	Slight or 1-10% pop. decline	Low (long-term)
6.1 - Recreational activities	Restricted (11-30%)	Slight or 1-10% pop. decline	Low (long-term)
7 - Natural system modifications	Restricted (11-30%)	Serious or 31-70% pop. decline	High (continuing)
7.2 - Dams & water management/use	Restricted (11-30%)	Serious or 31-70% pop. decline	High (continuing)
7.2.4 - Abstraction of surface water (unknown use)	Restricted (11-30%)	Serious or 31-70% pop. decline	High (continuing)

Roadless Areas (1)

Nevada (1)

Area	Forest	Acres
Stirling - Johnnie	Humboldt-Toiyabe National Forest	1,449

References (4)

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.
Hershler, R., H.-P. Liu and C. Bradford. 2013. Systematics of a widely distributed western North American springsnail, Pyrgulopsis micrococcus (Caenogastropoda, Hydrobiidae), with descriptions of three new congeners. ZooKeys 330:27-52.
U.S. Fish and Wildlife Service (USFWS). 2021. Endangered and Threatened Wildlife and Plants; 17 Species Not Warranted for Listing as Endangered or Threatened Species. Federal Register 86(184):53255-53261.

Pyrgulopsis turbatrix

Habitat

Ecology

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