Fluminicola multifarius
Hershler, Liu, Frest, and Johannes, 2007
Shasta Pebblesnail
G3VulnerableGlobal Rank
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.866912
Element CodeIMGASG3540
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
Endemicendemic to a single nation
KingdomAnimalia
PhylumMollusca
ClassGastropoda
OrderLittorinimorpha
FamilyLithoglyphidae
GenusFluminicola
Concept ReferenceHershler, R., H.-P. Liu, T.J. Frest, and E.J. Johannes. 2007. Extensive diversification of pebblesnails (Lithoglyphidae: Fluminicola) in the upper Sacramento River basin, northwestern USA. Zoological Journal of the Linnean Society 149:371-422.
Taxonomic CommentsPopulations of F. multifarius in the Rogue basin were referred to as the Chinquapin pebblesnail, Emigrant pebblesnail, Keene Creek pebblesnail, Little Butte pebblesnail, and Pilot Rock pebblesnail by Frest and Johannes (2000, 2004, 2005) (Hershler et al. 2017).
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2026-04-21
Change Date2026-04-21
Edition Date2026-04-21
Edition AuthorsT. Cornelisse
Threat ImpactHigh
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences21 - 80
Rank ReasonsThis species has a moderate range and number of known occurrences but it is subject to many likely threats and population trends are unknown.
Range Extent CommentsThis species occurs in central Oregon, northern California, and western Nevada, USA (RARECAT 2025; NatureServe 2026). In California, this species occurs in the Sacramento River headwater region (as far downflow as Conant), and a few sites in the upper reaches of the McCloud River drainage (Hershler et al. 2007). Records from the upper Rogue River basin south of Little Butte Creek, Oregon, extend the geographic range of this species about 80 km northward from the Sacramento River headwater region (Hershler et al. 2017).
Occurrences CommentsThis species is known from at least approximately 46 occurrences using a 2 km separation distance and records from 1993-2023 (RARECAT 2025; NatureServe 2026).
Threat Impact CommentsThis species is threatened by water impoundments, logging, grazing, and climate change impacts may affect freshwater aquatic snails, though there is insufficient evidence that these threats are greatly impacting this specific species (USFWS 2012; ORBIC 2024).
Ecology & Habitat
Habitat
This species is found in small to medium-sized springs and spring-influenced creeks (ORBIC 2024; NatureServe 2026).
Other Nations (1)
United StatesN3
| Province | Rank | Native |
|---|
| Nevada | SNR | Yes |
| Oregon | S2 | Yes |
| California | SNR | Yes |
References (8)
- 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., and D. W. Sada. 2002. Biogeography of Great Basin aquatic snails of the genus <i>Pyrgulopsis</i>. Smithsonian Contributions to the Earth Sciences 33:255-276.
- Hershler, R., H-P Liu, and N. Hubbart. 2017. Two new species of Fluminicola (Caenogastropoda, Lithoglyphidae) from southwest Oregon, USA, and a range extension for <i>F. multifarius</i>. ZooKeys 679:1-20.
- Hershler, R., H.-P. Liu, T.J. Frest, and E.J. Johannes. 2007. Extensive diversification of pebblesnails (Lithoglyphidae: <i>Fluminicola</i>) in the upper Sacramento River basin, northwestern USA. Zoological Journal of the Linnean Society 149:371-422.
- NatureServe. 2026. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
- Oregon Biodiversity Information Center (ORBIC). 2024. Element Subnational Ranking Form in Biotics 5 database. NatureServe, Arlington, Virginia.
- <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
- U.S. Fish and Wildlife Service (USFWS). 2012. Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition to List 14 Aquatic Mollusks as Endangered or Threatened. Federal Register 17(181):57922-57948.