Hershler (no date) called this species Pyrgulopsis new species 46. Hershler (1998) described the species as Pyrgulopsis nonaria and suggested the common name Ninemile pyrg for it.
The type locality for the species is "[s]pring, east side of Ninemile Reservoir, Sanpete Valley, San Pete [sic] County, Utah, T 19S, R 2E, NW ¼ section 9"; the holotype, USNM 883566, was collected 15 July 1993 (Hershler 1998).
No subspecies have been proposed in this species.
Status in Utah
This species occurs in 2 springs, not far apart, near Ninemile Reservoir, Sanpete County (Hershler no date, 1998).
Hershler (no date) noted that this species is "abundant" in one of the two springs. However, its overall population, compared with other organisms, must be very low due to its extremely restricted habitat and distribution.
Hershler (no date) reported disturbance of one of the two known sites inhabited by this species, the type locality (Hershler 1998), to be "slight". However, the limited occurrence of this species and the vulnerability of its habitat suggest that potential threats to the species are great. Population trend in this species is unknown.
Inventory of other springs near Ninemile Reservoir may be of use.
Considering the proximity to Ninemile Reservoir of the two springs inhabited by this species, it is possible that the filling of the reservoir may have destroyed other occurrences of the species by inundating springs in which they occurred.
Habitats Utilized in Utah
Hershler (1998) wrote: "The type locality is a shallow, broad, mineralized (1213 micromhos/cm) rheocrene emptying into Ninemile Reservoir." Hershler (no date) reported the temperature of this spring (the type locality) as 12 degrees C and its elevation as 5,540 ft.