Described as Cudonia monticola, based on collections from Washington, USA (Mains 1940). It was transferred into the genus Pachycudonia (Imai 1950). Genetic studies (Ge et al. 2014) suggest that Pachycudonia can be considered a synonym of Cudonia.
There is some question if C. grisea is a distinct species; modern taxonomic work is needed on this group, and if they are distinct, past collections need to be reexamined, as identification features are lacking between C. monticola and C. grisea.
Cudonia monticola is an uncommon species in western North America; occurring in the Pacific Northwest, and across the western mountains.
Currently known from around 100 records from ~60 locations. Based on the widespread nature, number of collections, and no noted decline, it would be tough to list as anything other than Least Concern (LC); or Data Deficient (DD) because of taxonomic issues.
Widespread in western North America; from British Columbia, Canada south into northern California on the coast and Coast Range, and continuing south into the northern Sierra Nevada; throughout the Cascade Range in Washington and Oregon, and the Rocky Mountains from Idaho south into Arizona.
Population is widespread; but apparently uncommon. Currently known from ~100 records from ~60 locations (Siegel et al. 2019, Mycoportal 2021). Data to assess trends is lacking, but based on recent observations, no decline has been noted.
Population Trend: Stable
Scattered or in small clusters on conifer duff, moss, or small woody debris in mature conifer forest. Fruiting in spring and early summer, typically from snowmelt moisture.
Logging or other disturbance; such as stand replacing fires.
This species is included on the US Forest Service Northwest Forest Plan sensitive species list (Castellano et al. 2003)
modern taxonomic work on Cudonia; especially regarding C. monticola and C. grisea. A better understanding of ecology and range of this species. Population trends.
Castellano, M., Cázares, E., Fondrick, B. and Dreisbach, T. 2003. Handbook to Additional Fungal Species of Special Concern in the Northwest Forest Plan. General Technical Report PNW-GTR-572. United States Department of Agriculture.
Ge, Z.W., Yang, Z.L., Pfister, D.H., Carbone, M., Bau, T. et al. 2014. Multigene Molecular Phylogeny and Biogeographic Diversification of the Earth Tongue Fungi in the Genera Cudonia and Spathularia (Rhytismatales, Ascomycota). PLOS ONE 9(8): e103457. https://doi.org/10.1371/journal.pone.0103457
Imai, S. 1950. On the genus of Cudonia constrictospora S. Ito et Imai. Botanical Magazine Tokyo 63(749): 234–235.
Mains, E.B. 1940. New and unusual species of the Geoglossaceae. American Journal of Botany 27: 322-330.
MyCoPortal. 2021. http://mycoportal.org/portal/index.php. Accessed on February 03.
Siegel, N., Vellinga, E.C., Schwarz, C., Castellano, M.A. and Ikeda, D. 2019. A Field Guide to the Rare Fungi of California’s National Forests. Bookmobile: Minneapolis, MN. 313 p.