P. algida was described as a distinct species by L. Malyshev in 1966. The depicted specimens were collected by himself in the Putorana Mountains (Russia, Siberia, 300 km E of Norilsk, lower Jenissej region, 300-800m) in August 1970. Unfortunately the hibernacula perished as I didn't keep them cold enough for a long time. They need (as also P. variegata) 10-15 centigrades below the freezing point during 9-10 months.