, the Shortface Lanx, was formerly widespread in the lower Columbia River, Snake River, and a few major tributaries within western North America. In recent years, the species has been extirpated from many former sites due to habitat alteration (Frest & Johannes, 1995). The current global conservation status rank is G2 - critically imperilled, at high risk of extinction (NatureServe, 2015).
This species was first reported from British Columbia as Ancylus kootaniensis by Baird (1863), based on collections made by Lord from the Kootenay River in southeast British Columbia (Natural History Museum Collections). The species was not documented in the province again until Clarke (1981) reported its presumed occurrence in the Columbia River at Trail based on the finding of a broken shell. It was not until 2009 that live specimens were collected at Trail (Royal BC Museum Collections).
This species is generally found in unpolluted, swift-flowing, highly oxygenated water on boulder-gravel substrate, often in the vicinity of rapids, in small to large rivers (Frest & Johannes, 1993).
Note Author: Ian Gardiner