Species: Helisoma anceps
Two-ridge Rams-horn
Species
Encyclopedia of Puget Sound
Classification
Kingdom
Animalia
Phylum
Mollusca
Class
Gastropoda
Order
Basommatophora
Family
Planorbidae
Genus
Helisoma
NatureServe
Classification
Other Global Common Names
hélisome à deux carènes
Informal Taxonomy
Animals, Invertebrates - Mollusks - Freshwater Snails
Formal Taxonomy
Animalia - Mollusca - Gastropoda - Basommatophora - Planorbidae - Helisoma - was not included in the assessment (Albrecht et al., 2007). Exhibits considerable variation over its wide range which has resulted in numerous subspecies that may not be taxonomically valid.
Ecology and Life History
Habitat Type Description
Freshwater
Migration
false - false - false
Non-migrant
false
Locally Migrant
false
Conservation Status
NatureServe Global Status Rank
G5
Global Status Last Reviewed
2008-10-09
Global Status Last Changed
1999-09-14
Distribution
Conservation Status Map
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Global Range
H - >2,500,000 square km (greater than 1,000,000 square miles) - H - Burch (1989) lists distribution as throughout North America from James and Hudson Bays south to Georgia, Alabama, Texas and northwestern Mexico, west to southwestern Northwest Territories, Alberta and Oregon for the nominal subspecies; and Isle Royale, Lake Superior, and the adjacent portions of Ontario north and west of Lake Superior in parts of the Albany, Attawapiskat and Winnipeg River systems for subspecies <i>Helisoma anceps royalense</i>.
Global Range Code
H
Global Range Description
>2,500,000 square km (greater than 1,000,000 square miles)