Gyroporus purpurinus

[ Basidiomycetes > Boletales > Gyroporaceae > Gyroporus . . . ]

by Michael Kuo

For some reason, this is one of those mushrooms I always want to find--and only rarely can. I don't know how many times I have excitedly stooped down to pick it, only to discover that I am looking at one of several purplish Tylopilus species. Gyroporus purpurinus has yellowish spores, and therefore has a pore surface that eventually becomes pale yellow--while Tylopilus pore surfaces are typically pinkish by maturity.

Why I get so excited about Gyroporus purpurinus, I don't know. It's a tiny little purplish red bolete, and I frankly have real doubts about its status as a separate "species"; not a lot, other than the color, separates it from Gyroporus castaneus, which is much more common and which, as its name suggests, is brown. Neither testing chemical reactions nor microscopic analysis provides a better means of separating the two mushrooms than simply observing that one is purplish red and the other is brown.

Description:

Ecology: Mycorrhizal with hardwoods ()but sometimes reported under conifers); growing alone, scattered, or gregariously; summer and fall; fairly widely distributed east of the Rocky Mountains, and reported in Mexico.

Cap: 2-8 cm; convex, becoming broadly convex or nearly flat in age; dry; smooth or slightly velvety; sometimes becoming slightly cracked in age (like me, according to my friends); purplish red.

Pore Surface: Whitish at first, becoming pale yellow; not bruising; 1-4 pores per mm; tubes to 8 mm deep.

Stem: 3-6 cm long; .5-1 cm thick; more or less equal, sometimes tapering to apex; dry; brittle; hollowing; colored like the cap; not bruising; not reticulate.

Flesh: White; not staining on exposure.

Odor and Taste: Not distinctive.

Chemical Reactions: Iron salts negative on cap surface, negative to very pale orangish on flesh; KOH erasing some of the pigment on the cap surface, negative to grayish on flesh; ammonia negative on cap surface and flesh.

Spore Print: Yellow.

Microscopic Features: Spores 8-11 x 5-7 µ; smooth; elliptic to oval.

REFERENCES: (Snell, 1936) Singer, 1945. (Singer, 1945; Snell & Dick, 1970; Smith & Thiers, 1971; Smith, Smith & Weber, 1981; Arora, 1986; Phillips, 1991/2005; Lincoff, 1992; Both, 1993; Horn, Kay & Abel, 1993; Bessette, Roody & Bessette, 2000.) Herb. Kuo 09289620, 07230306, 06300709, 07050802, 07120810.

Further Online Information:

Gyroporus purpurinus in Smith & Thiers, 1971
Gyroporus purpurinus at Roger's Mushrooms

© MushroomExpert.Com

Cite this page as:

Kuo, M. (2003, August). Gyroporus purpurinus. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/gyroporus_purpurinus.html