Oreohelix strigosa

Considerable confusion exists in the literature, especially in older works, concerning Oreohelix strigosa and Oreohelix subrudis, which were frequently confused, O. subrudis having often been included in O. strigosa, at least until the mid-1930s. Older literature is further complicated by use of the name "Oreohelix cooperi", formerly applied variously to both O. strigosa and O. subrudis; the name cooperi has also been used for various races of each of both species, but, as used now, this name has been restricted to one race of O. strigosa.

Although Brandauer (1988), based on both external (shell) and internal (genitalia and radula) morphology, concluded that Oreohelix subrudis should be considered only a form (or "morph") of Oreohelix strigosa (i.e., that the two are synonyms), Rees (1988) found that "[c]onsistent and distinct differences in enzyme banding patterns between these two species were revealed by electrophoresis" and "allozyme variation can be assessed to reliably distinguish between O. strigosa and O. subrudis."

Pilsbry (1939) discussed 10 subspecies and numerous "forms" and "varieties" of Oreohelix strigosa, but his subspecies concept was very different from the one that is in current taxonomic use, many of Pilsbry's subspecies now being regarded as mere "morphs". Richardson (1984) listed 25 subspecies (including one fossil race) of Oreohelix strigosa. It is questionable whether all of these subspecies merit recognition, for O. strigosa is one of the most plastic and polymorphic of all gastropods, exhibiting surprisingly great variation even within local populations.

Weaver et al. (2008) concluded that specimens identified as Oreohelix peripherica wasatchensis are not monophyletic based on molecular and radular data; and instead show two distinct clades within "O. p. wasatchensis", one that nests within Oreohelix strigosa, and one that is a sister group to Oreohelix peripherica peripherica. Their evidence indicates Oreohelix strigosa may not be a monophyletic group and add that taxonomic revision of the species is necessary.

Widespread, abundant, and, within its range, apparently one of the most secure of all mollusk species, including exotic introductions.

Occurs generally throughout the mountainous areas of interior western North America. Known from southeastern British Columbia, extreme southeastern Alberta, eastern Washington, extreme northeastern Oregon, northern and extreme southeastern Idaho, western Montana, extreme western South Dakota (i.e., the Black Hills), extreme western Wyoming, extreme eastern Nevada, nearly all of Utah, Colorado except the eastern third, northern and eastern Arizona, and northern and central New Mexico (Pilsbry 1939; see also Bequaert and Miller 1973). Known also as a Pleistocene fossil in Iowa and Illinois (Pilsbry 1939, Morrison 1943, Frest and Rhodes 1981). Pilsbry (1939) commented on the discontinuities in the northern and northwestern parts of its range (i.e., Washington and Oregon). Disjunct populations are also apparent at the northeastern and southern limits of distribution, some notable examples of such disjunct--probably Pleistocene relictual--populations being those in the Black Hills (South Dakota), the White Mountains (Arizona), and the Sierra Blanca (New Mexico).

Certainly well over 100 and possibly 1,000 or more extant occurrences. Pilsbry's dot map (1939, Figure 296) shows 106 specimen localities (for this species), and very many more are known. For example, in Utah alone only a small fraction of the extant occurrences are represented in Pilsbry's (1939) map. Distribution in Alberta is spotty: Cypress Hills with the next nearest location being Waterton Lake, then north of Pincher Creek (Lepitzki, 2001). Most recently, it was discovered in the Ktunaxa Traditional Territory in southeastern British Columbia (which extends from near Canada - U.S. border north to about 50 km north of Cranbrook) (Ovaska and Sopuck, 2009).

Generally protected from most anthropogenic threats by the unsuitablity of its habitat for development and other economic use; however, timber harvest within its habitat is very likely a threat. Fire represents a natural threat.