Phlegmacium ponderosum, also known as the Ponderous Cortinarius, is a species of mushroom producing fungus in the family Cortinariaceae.[1] It is very large and due to its thick stem it can be mistaken for Boletus edulis.
| Phlegmacium ponderosum | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Basidiomycota |
| Class: | Agaricomycetes |
| Order: | Agaricales |
| Family: | Cortinariaceae |
| Genus: | Phlegmacium |
| Species: | P. ponderosum
|
| Binomial name | |
| Phlegmacium ponderosum (A.H.Sm.) Niskanen & Liimat. (2022)
| |
| Synonyms | |
| |
Phlegmacium ponderosum | |
|---|---|
 | Gills on hymenium |
 | Cap is convex |
 | Hymenium is adnate |
 | Stipe is bare |
 | Spore print is yellow |
 | Ecology is mycorrhizal |
 | Edibility is not recommended |
Taxonomy
editIt was described in 1939 by the American mycologist Alexander H. Smith who classified it as Cortinarius ponderosus.[2]
In 2022 the species was transferred from Cortinarius and reclassified as Phlegmacium ponderosum based on genomic data.[3]
Description
editThis mushroom is one of the largest mushrooms in the family Cortinariaceae, with a convex cap that ranges from 10–30 cm (4–12 in)[4] and becomes plane in age. It often has an olive metallic tinge, and the surface is viscid, often with small rusty brown scales.[4] The margin is ocher and remains inrolled until the mushroom is fully mature. The flesh of the mushroom is yellow-white, thick and firm, with a mild to sour odor.[4] The gills are rusty brown, adnate[4] and slightly decurrent. The stalk is 8–20 cm (3–8 in) thick, 4–10 cm wide, and bulbous at the base.[4] It has a slimy yellow universal veil, and the cortina leaves a rusty brown hairy area on the upper stalk. The spores are brown and elliptical.[4]
Its edibility is unknown, but it is not recommended due to its similarity to deadly poisonous species.[4]
Cortinarius infractus is a similar species that usually has a smaller cap.[4]
Etymology
editThe specific epithet ponderosum (originally ponderosus) is named for the Pinus ponderosa trees which Smith observed the mushrooms growing under.[2]
Habitat and distribution
editSmith observed the mushrooms growing under Pinus ponderosa and Quercus (Oak) species near Cave City in Oregon and under Spruce trees near Crescent City, California.[2]
See also
editReferences
edit- ^ "Species Fungorum - Phlegmacium ponderosum (A.H. Sm.) Niskanen & Liimat". www.speciesfungorum.org. Retrieved 2023-01-14.
- ^ a b c Smith, Alexander H. (1939). "Studies in the Genus Cortinarius I". Contributions from the University of Michigan Herbarium. 2. Ann Arbor: University Herbarium, University of Michigan: 6 – via biodiversitylibrary.org.
- ^ Liimatainen, Kare; Kim, Jan T.; Pokorny, Lisa; Kirk, Paul M.; Dentinger, Bryn; Niskanen, Tuula (2022-01-01). "Taming the beast: a revised classification of Cortinariaceae based on genomic data". Fungal Diversity. 112 (1): 89–170. doi:10.1007/s13225-022-00499-9. hdl:2299/25409. ISSN 1878-9129.
- ^ a b c d e f g h Davis, R. Michael; Sommer, Robert; Menge, John A. (2012). Field Guide to Mushrooms of Western North America. Berkeley: University of California Press. pp. 261–262. ISBN 978-0-520-95360-4. OCLC 797915861.