(Pyrgulopsis robusta, Pyrgulopsis hendersoni, and Pyrgulopsis new species 6)
(Gastropoda: Sorbeoconcha: Hydrobiidae)
Profile prepared by The Xerces Society for Invertebrate Conservation
The Jackson Lake springsnail (Pyrgulopsis robusta), Harney Lake springsnail (Pyrgulopsis hendersoni), and Columbia springsnail (Pyrgulopsis new species 6) are three freshwater snails from the western United States. Each species is limted to an extremely small population with a very narrow habitat range. The three species have experienced population decline due to habitat loss and degradation, and are still threatened by numerous factors. The Xerces Society, along with several other conservation groups and individuals, submitted a petition to list these species as Threatened or Endangered under the federal Endangered Species Act in 2004.
petition to list these species
This information is adapted from the petition to list these springsnails as endangered (Bowler at al. 2004).
The Jackson Lake springsnail was once designated a Candidate for listing under the Endangered Species Act. It has a G1 Global Heritage Ranking.
The Harney Lake springsnail has a G1 Global Heritage Ranking; the Columbia springsnail has a G2 Global Heritage Ranking.
This information is adapted from the petition to list these species (Bowler et al. 2004).
Jackson Lake Springsnail: shell height 5.5-6.3 mm, 5-5.5 whorls, shell ovate- to narrowly-conic and large umbilicate, broader central teeth than other springsnail species, consistently smaller than Idaho and Columbia springsnails (Hershler 1994, Hershler and Liu 2004).
Harney Lake Springsnail: shell height 4-6.5 mm, 4.5-5.5 whorls, ovate- to low-conical shell; dark pigmentation; well developed oviduct coil rare, smaller than Idaho and Columbia springsnails (Hershler 1994, Hershler and Liu 2004).
Columbia Springsnail: distinctive penial features; yellow pigmentation, larger than Jackson Lake and Harney Lake springsnails (Frest and Johannes 1995a).
All of the species described below are in the family Hydrobiidae (Hershler and Liu 2004). The Jackson Lake springsnail was originally named Pomatiopsis robusta; the species was subsequently ascribed to the genus Amnicola (Pilsbry 1933), then to the genus Fontelicella (Gregg and Taylor 1965), and finally to the genus Pyrgulopsis (Hershler and Thompson 1987, Hershler 1994). The name Pyrgulopsis robusta is accepted today as the scientific name of the species (Turgeon et al. 1998), although a recent study suggests the species’name may be synonymous with Pyrgulopsis idahoensis, Pyrgulospis hendersoni, and Pyrgulopsis new species 6 (Hershler and Liu 2004).
The Harney Lake springsnail was discovered in 1929 and was described based on forms from springs south of Burns, Oregon. Originally named Paludestrina sp., the species was subsequently ascribed to the genus Amnicola (Pilsbry 1933), then to the genus Fontelicella (Gregg and Taylor 1965), and finally to the genus Pyrgulopsis (Hershler and Thompson 1987, Hershler 1994). The name Pyrgulopsis hendersoni remains valid (Turgeon et al. 1998), although a recent study suggest the species may be a synonym of Pyrgulopsis robusta (Hershler and Liu 2004).
The Columbia springsnail was reported in 1995 as an unnamed species (Frest and Johannes 1995a). The species has been named Pyrgulopsis new species 6, but has not yet been formally named. The species is distinct from other related species by its unpigmented tentacles, common yellow and orange pigment granules on the body, and distinctive penile features (Id.). Although the species has not been formally named, a recent study suggests the species may be a synonym of Pyrgulopsis robusta (Hershler and Liu 2004).
A recent taxonomic study suggests the Jackson Lake, Harney Lake, and Columbia springsnail species are actually a part of a larger clade, the Natricola clade, which also includes the Idaho springsnail. The study synonimizes all four springsnails and ascribes them all as Pyrgulopsis robusta, the Jackson Lake springsnail, which is the senior taxon. Scientists have expressed significant concerns over the conclusions of Hershler and Liu (2004). Citing obvious morphological differences, ecological differences, behavioral differences, and long-term biogeographical isolation, scientists have flatly rejected the findings of Hershler and Liu (2004) (Bowler 2003, Bowler et al. 2004).
Information adapted from the petition to list these species (Bowler et al. 2004).
Jackson Lake springsnail: occurs in broad daylight (i.e., not photophobic) on surface of rocks; perilithon grazer (Frest and Johannes 1995a). Lives in cold springs in and around Jackson Lake and in cold spring-influenced creeks with sand, gravel, or cobble substrate; sometimes dense cress (Rorippa sp.) beds common; predominantly a crenophile, although found in lake habitats as well (Frest and Johannes 1995a, Bowler et al. 2004).
Harney Lake springsnail: aufwuchs grazer, apparently not photophobic, mud specialist (Frest and Johannes 1995a, Frest Bowler et al. 2004). Lives in mildly thermal springs and spring pools with typically fine substrates; which are generally shallow and generally have moderate flow; dense cress (Rorippa sp.) beds common; considered a crenophile, meaning it prefers spring environments (Frest and Johannes 1995a, Bowler et al. 2004).
Columbia springsnail: occurs on undersides of rocks, most likely photophobic; perilithon grazer (Frest and Johannes 1995a). Lives in the lower Columbia River in areas of relatively deep cold water with constant flow and a rocky substrate; macrophytes uncommon; considered an amniphile (Frest and Johannes 1995a, Bowler et al. 2004).
Adapted from petition to list these species (Bowler et al. 2004).
This information is adapted from the petition to list these species (Bowler et al 2004).
All three of these springsnail species have experienced habitat loss and degradation throughout their ranges. Causes of habitat loss have included spring development, domestic livestock grazing, groundwater withdrawal, water pollution, and dams. Their populations may have also been impacted by collections for scientific purposes, predation by other animals, herbicide and pesticide use, the introduction and spread of invasive species, and climate change. These three springsnail species are especially at risk for extinction because their remaining populations are either small, isolated, and/or fragmented.
All four snails need protection under the Endangered Species Act, regardless of whether they are all the same species. Protecting the Jackson Lake, Harney Lake, and Columbia springsnails under the Endangered Species Act will lead to many benefits. Most notably, protection under the Endangered Species Act will ensure these species and the ecosystems they depend upon will receive adequate protection from the threat of continued loss and degradation. Protection of the species not only brings increased protection for the snails and their habitats, but increased protection for other species that also depend upon healthy ecosystem, such as native trout. And, because there is a direct link between healthy populations of snails and a healthy environment, protection of the Jackson Lake, Harney Lake, and Columbia springsnails will ultimately lead to increased protection for our own communities for future generations.
Bowler, P. 2003. Comments upon the report by Hershler and Liu on the “Taxonomic Status of the Idaho Springsnail (Pyrgulopsis idahoensis).”Letter submitted June 16, 2003 to Mr. Stephen Duke, Program Manager for Endangered Species and Private Lands, United States Department of the Interior, Fish and Wildlife Service, Snake River Fish and Wildlife Office, 1387 South Vinnell Way, Room 368, Boise, Idaho 83709.
Bowler, P., Biodiversity Conservation Alliance, Center for Biological Diversity, Center for Native Ecosystems, Western Watersheds Project, The Xerces Society. 2004. Petition to List the Jackson Lake Springsnail (Pyrogulopsis robusta), Columbia springsnail (Pyrgulopsis hendersoni) and Columbia springsnail (Pyrgulopis new species 6) as Threatened or Endangered.
Frest, T.J. and E.J. Johannes. 1995a. Interior Columbia Basin Mollusk Species of Special Concern. Final Report to Interior Columbia Basin Ecosystem Management Project. Deixis Consultants, 2517 NE 65th St, Seattle, WA 98115. 362 p.
Gregg, W.O. and D.W. Taylor. 1965. Fontelicella (Prosobranchia Hydrobiidae), a new genus of west American freshwater snails. Malacologia 3: 103-110.
Hershler, R. 1994. A Review of the North American Freshwater Snail Genus Pyrgulopsis (Hydrobiidae). Smithsonian Contributions to Zoology 554.
Hershler, R. and H. Liu. 2004. Taxonomic reappraisal of species assigned to the North American freshwater gastropod subgenus Natricola (Rissooidea: Hydrobiidae). The Veliger 47(1): 66-81.
Hershler, R. and F.G. Thompson. 1987. North American Hydrobiidae (Gastropoda: Rissoacea): redescription and systematics relationships of Tryonia Stimpson, 1865 and Pyrgulopsis Call and Pilsbry, 1886. The Nautilus 101: 25-32.
Pilsbry, H.A. 1933. Amnicolidae from Wyoming and Oregon. The Nautilius 47: 9-12.
Turgeon, D.D., A.E. Bogan, E.V. Coan, W.K. Emerson, W.G. Lyons, W.L. Pratt, C.F.E. Roper, A. Scheltema, F.G. Thompson and J.D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: mollusks. American Fisheries Society Special Publication 26. 526 pp.