Paxillus filamentosus

Paxillus filamentosus, commonly known as the alder roll-rim, is a basidiomycete fungus which is associated with alder (Alnus) in northern Europe and southwestern Greenland,^[1] and North America.^[2] It closely resembles Paxillus involutus, but its fruit bodies are generally smaller.^[3]

Paxillus filamentosus
Scientific classification
Kingdom:	Fungi
Division:	Basidiomycota
Class:	Agaricomycetes
Order:	Boletales
Family:	Paxillaceae
Genus:	Paxillus
Species:	P. filamentosus
Binomial name
Paxillus filamentosus (Scop.) Fr. (1838)
Synonyms
Agaricus filamentosus Scop. (1772) Paxillus rubicundulus P.D.Orton (1969)

Paxillus filamentosus Mycological characteristics
	Gills on hymenium
	Cap is depressed
	Hymenium is decurrent
	Stipe is bare
	Spore print is brown
	Ecology is mycorrhizal
	Edibility is unknown

Some sources regard Paxillus rubicundulus as a synonym,^[4] but MycoBank and Index Fungorum treat it as different species.^[5][6]