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Vespericola shasta

(S.S. Berry, 1921)

Shasta Hesperian

G3Vulnerable Found in 1 roadless area NatureServe Explorer →
G3VulnerableGlobal Rank
LowThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.115179
Element CodeIMGASA4070
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
Endemicendemic to a single state or province
KingdomAnimalia
PhylumMollusca
ClassGastropoda
OrderStylommatophora
FamilyPolygyridae
GenusVespericola
Concept Reference
Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2020-11-12
Change Date2020-11-12
Edition Date2020-11-12
Edition AuthorsK. Hunting
Threat ImpactLow
Range Extent250-1000 square km (about 100-400 square miles)
Number of Occurrences6 - 20
Rank Reasons
While the Shasta hesperian is a relatively narrow endemic, it is currently known from 78 sites which is a substantial increase in the number of known locations since the initial assessment.
Range Extent Comments
The Shasta hesperian is known from 78 sites in the upper Shasta, Trinity, and Pit River watersheds (USFWS 2011, Frest and Johannes 1993) in Shasta and Trinity Counties, California. Burke et all (1999) reported the distribution as 7 known sites with the remainder of the sites mentioned in USFWS (2011) are from unknown origin but presumably from Survey and Manage Reports for specific projects or from project monitoring (e.g., Pacific Gas and Electric Hydroelectric Generation license requirement monitoring on the Pit River). USDA and USDI 2007 report the Shasta herperian from 78 sites again presumably from Strategic Surveys and other project-related survey detections. All known locations are within the range of the northern spotted owl (Stix occidentalis caurina).
Occurrences Comments
The Shasta hesperian is distributed primarily in riparian areas in scattered locations throughout the upper Shasta, Trinity, and Pit River watersheds, in Shasta and Trinity Counties, California.
Threat Impact Comments
The Shasta hesperian occurs primarily in riparian zones in forested areas of Shasta and Trinity Counties. Timber harvest rules provide for set backs in riparian zones which would provide some protection for existing locations. USDA and USDI (2007) suggest that the existing level of protection of known sites are sufficient to support stable populations.
Ecology & Habitat

Diagnostic Characteristics

Distinguished from other species by its penial sheath, which not only encloses the entire penis, but also a portion of the proximal epiphallus, and by its minuscule, conical, pointed verge (Cordero and Miller, 1995).

Habitat

The Shasta hesperian is found along river edges almost in the water under bark and debris, calciphile (Cordero and Miller 1995).
Terrestrial Habitats
Woodland - Mixed
Other Nations (1)
United StatesN1
ProvinceRankNative
CaliforniaS3Yes
Threat Assessments
ThreatScopeSeverityTiming
5 - Biological resource useSmall (1-10%)Negligible or <1% pop. decline—
5.3 - Logging & wood harvestingSmall (1-10%)Negligible or <1% pop. decline—

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Roadless Areas (1)
California (1)
AreaForestAcres
Devils RockShasta-Trinity National Forest16,209
References (6)
  1. Burke, T.E., J.S. Applegarth, and T.R. Weasma. 1999. Management recommendations for survey and manage terrestrial mollusks. Ver. 2.0. Report submitted to USDI Bureau of Land Management, Salem, Oregon, October 1999. Unpaginated.
  2. Cordero, A.M. and W.B. Miller. 1995. Reproductive anatomy of <i>Vespericola shasta</i> (Berry, 1921) (Gastropoda: Pulmonata: Polygyridae), and descriptions of two new species of Vespericola from northern California. Veliger, 38(4): 304-311.
  3. Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.
  4. USDA and USDI. 2007. Final Supplement to the 2004 Supplemental Environmental Impact Statement to Remove or Modify the Survey and Manage Mitigation Measure Standards and Guidelines. Volume 1 - Chapters and Text. U.S. Forest Service National Forests in Regions 5 and 6 and Bureau of Land Management Districts in Washington, Oregon, and California Within the Range of the Northern Spotted Owl. Portland, Oregon.
  5. U.S. Fish and Wildlife Service (USFWS). 2011. Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition to List 29 Mollusk Species as Threatened or Endangered with Critical Habitat; Proposed Rule. Federal Register 76(193):61826-61853.
  6. U.S. Fish and Wildlife Service (USFWS). 2023. National Listing Workplan. Online. Available: https://www.fws.gov/project/national-listing-workplan