Cortinarius sebaceus

Description:

Cortinarius is the largest genus of mushrooms in the world, containing an astounding number of species (often estimated well over a thousand). Although the mushrooms in Cortinarius are very diverse, it is usually pretty easy to figure out when you are looking at one, once you get the hang of it. First, they have cortinas covering their gills when young (hence the name of the genus); sometimes the tiny fibers of the cortina are ephemeral and disappear, but they frequently collapse against the stem to create a ring zone. Secondly, the spore print is rusty brown and, as a result of the rusty brown spores, the mature gills of Cortinarius mushrooms are usually also rusty brown. Finally, they are terrestrial and mycorrhizal, so you will only find them in association with trees

Habitat:

Since members of the genus Cortinarius are mycorrhizal, they have evolved with their symbionts and therefore occupy limited ecological niches. Because some, if not all, species are partial to particular trees or groups of related trees, careful ecological field notes and documentation are a must when collecting Cortinarius specimens for identification, especially when collecting in notoriously "mixed" woods like montane, boreal, or coastal ecosystems. In northern Michigan, for example, I have found Cortinarius armillatus, which is an obligate associate of birch, in woods that appeared to be composed only of aspens, hemlock, and balsam fir . . . only to return to the location and discover a tiny, three-foot birch sapling a few feet away from my collection location ( http://www.mushroomexpert.com/cortinariu... )

Notes:

Several mushrooms in the genus Cortinarius are poisonous, mainly because they cause acute tubulointerstitial nephritis. Some are even lethal, such as Cortinarius rubellus and Cortinarius orellanus. Therefore, a common rule when it comes to mushrooms from this genus is that none of them should be eaten. However, some species—notably the giant of the genus, Cortinarius praestans and the gypsy mushroom (Cortinarius caperatus)—are edible and appreciated in several European countries. The toxin in Cortinarius species, orellanine is easy to detect because it is fluorescent. It has been found in at least 34 Cortinariaceae (wikipedia) ( http://www.mycobank.org/MycoTaxo.aspx?Li... ), ( http://mushroomhobby.com/Gallery/Cortina... ),