Taxonomy
Specimens of the Kanab ambersnail were first collected in 1909 by James Ferriss from: "The Greens", 10 kilometers (6.2 mi) above Kanab, Utah on Kanab Wash, on a wet ledge among moss and Cypripediums. These specimens were originally thought to belong to the species Succinea hawkinsi.
Pilsbry (1948) transferred these specimens to the genus Oxyloma and erected the subspecies kanabensis in the species haydeni for them. Arthur Clarke (1991) notes that Pilsbry’s decision to accord the Kanab ambersnail subspecific status was preliminary, and that, as Pilsbry himself noted, “its taxonomic status should be reevaluated.”
Clarke (1991) and Shei K. Wu (Colorado Museum of Natural History, Boulder, Colorado, pers. comm. 1992, 1995) suggest that the Kanab ambersnail may deserve full species status. Earle Spamer (Academy of Natural Sciences of Philadelphia, Philadelphia, Pennsylvania, pers. comm. 1994) stated that although current published mollusk checklists (Turgeon et al. 1988 and Groombridge 1993) treat the Kanab ambersnail at species level rather that as a subspecies, nonetheless, until the criteria are derived (and published) by which the taxon can be known to be a separate species, it should continue to be called by its original name, the one published by Pilsbry (1948): Oxyloma haydeni spp. kanabensis. Despite this, NatureServe does list this taxon as a species.
Read more about this topic: Kanab Ambersnail