Wyoming lacks a rich molluscan fauna due to its considerable elevation, extremes of temperature, the short period between killing frosts, scanty moisture, and intermittent creeks. Recent mollusks found in the state total 42 genera (109 species), including 6 genera (23 species) of bivalves, 15 genera (42 species) of freshwater gastropods, and 21 genera (44 species) of land gastropods. Synonymy, the counties in which each species was collected, and habitat notes are given.
Beetle, Dorothy E.
"Checklist of Recent Mollusca of Wyoming, USA,"
Great Basin Naturalist: Vol. 49
, Article 23.
Available at: http://scholarsarchive.byu.edu/gbn/vol49/iss4/23