Tricholomataceae sp.-?

The truth is, this family of gilled mushroom genera was always more of a taxonomical convenience than a "natural" group, consisting of mushrooms that were "brought together more on a set of negative characters than any one positive uniting factor" (Stuntz, 1973). In other words, if your pale-spored, gilled mushroom was not an Amanita, a Limacella, a Lepiota, a Russula, a Milky Cap, or a Waxy Cap, it belonged in the Tricholomataceae.

Because the Tricholomataceae was always more of a taxonomical dumping ground than a natural family, it should come as no surprise that recent DNA studies have disrupted it entirely. Many new families, including the Omphalotaceae, the Physalacriaceae, the Marasmiaceae, the Mycenaceae (and others) have been erected as a result of genetic analysis--and some of these families contain mushrooms that used to belong outside the "Tricholomtaceae." Family status is currently undecided for many mushrooms in the "Family Formerly Known as the Tricholomataceae," and various "clades" group together the mushrooms not yet granted (insert)-aceae status. On top of the genetic studies, microscopic analysis has separated out the Xerulaceae on the basis of sarcodimitic tissues (see the photo on the page for Gerronema strombodes). To see the long list of genera that are officially included in the Tricholomataceae at the moment
( http://www.mushroomexpert.com/tricholomataceae.html )