SPECIES FACT SHEET
Species Common Name: Turban pebblesnail
Species Scientific Name: Fluminicola turbiniformis (Tryon, 1865)
Phylum: Mollusca
Class: Gastropoda
Order: Neotaenioglossa
Family: Hydrobiidae
OR/WA BLM and FS Region 6 Units where Suspected or
Documented:
Documented from three locations on the Fremont/Winema National
Forest.
Technical Description:
Small shell ovate- to narrow-conic; height 3.1 – 4.3 mm; 3.5 – 4.0 whorls;
body whorl highly convex, periphery rounded. Radial structure of
microscopic growth lines. Periostracum light green or brown. Aperture
large, ovate; dorsal lip thin, weakly sinuate, parietal lip complete, thick,
usually detached from body whorl, columnar lip swelling; umbilicus
narrow, weakly excavated.
Life History:
Separate sexes, (probably) semelparous – live 1-2 years, breeds and dies.
Population turn over is probably greater than 90%.
Reproduce by copulation and cross-fertilization. Eggs are laid from
spring to autumn in gelatinous capsules attached to plants, stones, or
other objects.
Feed by scraping bacteria, diatoms and other microscopic organisms
from rock and aquatic plant surfaces. Present all year, but not active in
winter. Individuals have no lungs or gills with respiration through the
mantle cavity. Have low tolerance for hypoxia and anoxia.
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Range, Distribution (Current and Historic), and Abundance:
Documented from three locations on the Fremont/Winema National
Forest. Also documented from Roaring Springs, in Catlow Valley, west
side of Steens Mountains, Harney County, OR. on private land within the
Burns BLM District; no similar habitat is present on BLM land
ownership however, so the species is not suspected to occur on Burns
BLM land. Other similar specimens from Crane Lake Valley and Surprise
Valley in NE California are better assigned to one or more other,
undescribed species.
Habitat Associations:
Found to date only in one, large oligotrophic spring complex with very
cold water, in semi-arid sage scrub. Abundant Rorippa and Mimulus
flora present. Substrate is mud, basalt gravel, bedrock and cobble, with
bedrock predominate in area of occurrence.
Threats:
Water diversion of springs for domestic and livestock use; grazing which
causes direct mortality and sedimentation, and pollution; geothermal
development and pumping of groundwater resulting in lowered water
table and reduced spring output. Use of area by the public may also
result in trampling and water quality reductions.
Conservation Considerations:
Limit water diversions and grazing in area of spring runs which reduce
water quantity and may add sediment, nutrients and other pollutants to
water. Avoid new construction of structures which slow water flow and
cause reduced oxygenation. Limit water withdrawl from aquifer which
sustains spring flow and geothermal exploration.
Prepared by: Nancy Duncan, April 2008
Edited by Rob Huff, March 2011
References:
Frest, T. J., and E. J. Johannes. 1995. Interior Columbia Basin mollusk
species of special concern. Final report: Interior Columbia Basin
Ecosystem Management Project, Walla Walla, WA. Deixis Consultants,
Seattle, WA. Contract #43-0E00-4-9112. 274 pp. plus appendices.
Hershler, R. & T. J. Frest. 1996. A review of the North American
freshwater snail genus Fluminicola (Hydrobiidae). Smithsonian
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Contributions of Zoology: No. 583 (Article not seen, citation from Lee
2000a. Freshwater molluscs of British Columbia: assessments for all
known or potential taxa. Unpubl. rep. submitted to the BC Conservation
Data Centre, Minist. Envrion., Lands and Parks, Victoria, BC. 107pp.)
Tryon, G.W. 1865. Descriptions of New Species of Amnicola,
Pomatiopsis, Somatogyrus, Gabbia, Hydrobia, and Rissoa. American
Journal of Conchology. 1:219-222.
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