DOWNLOAD full IUCN Assessment as PDF

Common name(s): English: Pale-belly Frost Lichen

ASSESSMENT JUSTIFICATION [criteria: B2ab(i,ii,iii,iv,v); C2a(i)]

Physconia subpallida occurs in severely fragmented locations throughout eastern North America. Its Extent of Occurrence, Area of Occupancy, and extant and quality of its habitat have declined substantially over the past century due to widespread logging, air pollution, and development. Now, there are fewer than 2,500 individuals left (total population size estimated at 400 mature individuals) after substantial declines, and most subpopulations are very small, consisting of 1-5 individuals, with the largest subpopulation consisting of fewer that 250 mature individuals. The habitat for this species is now very limited throughout its range as it appears to require old-growth deciduous forests, which are rare and fragmented throughout its core range in south-eastern Ontario (Henry & Quinby 2010, McMullin2015, McMullin et al. 2016, Allen & McMullin 2019). The total Area of Occupancy [AOO] is estimated to be very small, with the known AOO only 260 km2, up to a potential maximum of 324 km². Therefore,this species is Endangered, B2ab(i,ii,iii,iv,v); C2a(i).

Assessor/s: McMullin, T., Allen, J. & Lendemer, J.; Reviewer/s: Stone, D.; Facilitator(s) and Compiler(s): Bishop, G. & Allen, J.

Bibliography:

Allen, J.L. & McMullin, R.T. (2019) Modeling algorithm influence o n the success of predicting newpopulations of rare species: Ground - proofing models for the Pale - Belly Frost Lichen (Physconia subpallida) in Ontario. Biodiversity and Conservation 28: 1853-1862.

CNALH. 2020. Consortium of North American Lichen Herbaria. Available at: https://lichenportal.org/cnalh/. (Accessed: 18 May).

COSEWIC (2009) COSEWIC assessment and status report on the Pale-bellied Frost Lichen Physconia subpallida in Canada. Committee on the Status of Endangered Wildlife in Canada, Ottawa, ON.

Environment Canada (2015) Recovery Strategy for the Pale-bellied Frost Lichen (Physconia subpallida) in Canada. Species at Risk Act Recovery Strategy Series. Ottawa.

Esslinger, T.L. (1994) New species and new combinations in the lichen genus Physconia in North America. Mycotaxon 51: 91-99.

Government of Canada (2020) Species At Risk Act. Government of Ontario. 2015. Pale-bellied frost lichen.

Henry, M. & Quinby, P. (2010) Ontario's Old-growth Forests. A Guidebook Complete with History,ecology and Maps. Fitzhenry and Whiteside Limited, Markham, Ontario.

IUCN (2020) The IUCN Red List of Threatened Species. Version 2020-3. Available at: www.iucnredlist.org. (Accessed: 10 December 2020).

Lewis , C.L. (2011) Recovery Strategy for the Pale - bellied Frost Lichen (Physconia subpallida) in Ontario. Ontario Recovery Strategy Series. Prepared for the Ontario Ministry of Natural Resources.

McMullin, R.T. (2015) A review of Physconia subpallida in Canada. Opuscula Philolichenum 14: 109-115.

McMullin, R.T., Allen, J.L. & Pagé, J.P. (2016) Physconia subpallida new to Québec, from Gatineau Park. Opuscula Philolichenum 15: 92-104.

Find out more about the IUCN Red List Categories and Criteria here.