Collybia brunneocephala

Collybia brunneocephala, also known as the brown blewit or brownit, is a species of gilled mushroom. Previously designated Clitocybe brunneocephala, the brownit and its lavender-colored cousin the wood blewit were reassigned to the genus Collybia in 2023.

As its name implies, the brownit is a brown-capped mushroom with light-beige gills. The cap is usually described as "lubricious" and often has a rubbery-translucent gloss without being sticky. The brownit also has a bit of a stumpy, short-legged quality, as the ratio of cap diameter to stipe height heavily favors the cap. The brownit flushes most frequently from December to March, and is most commonly observed in California in western North America. Often found in lawns and open meadows, sometimes in fairy rings, it also turns up under California native oaks and Monterey cypress.

The brownit is considered a "excellent" edible mushroom, but it can be confused with Entoloma lividoalbum, Entoloma sericatum, and Entoloma rhodopolium, all of which are poisonous. Brownits can also be mistaken for Collybia nuda (which it resembles in both "size and stature") and Clitocybe tarda, but can be distinguished by color and size. C. nuda often looks brown in age, but will retain undertones of lilac. Clitocybe tarda mushrooms are smaller than C. brunneocephala and will retain some hint of purple on the cap, unlike Collybia brunneocephala which stays in the color range from brown to light beige.

William A. Murrill originally described this species in 1913 as a Melanoleuca, based on a specimen collected by R. A. Harper in Alameda County, California. However, based on the minimal information provided, it was not included in later descriptions of Clitocybe species. The brownit was rediscovered by David Arora in Santa Cruz County, California, in the 1970s, and Howard E. Bigelow formally redescribed it in his 1982 Clitocybe monograph using Arora's specimens. There was already a Clitocybe harperi, so the Bigelow gave it a new name suggestive of its brown (brunneo-) head (-cephela). According to recent genetic studies by taxonomists in China, C. brunneocephala belongs to a subgenus designated Leucocalocybe, along with what were formerly designated Lepista personata, Lepista nuda, Lepista fibrosissima, Lepista sordida, and Collybia mongolica, "forming a strongly supported monophyletic clade (BP = 95%, PP = 1.00)."