Tricholoma muricatum Shanks
Mycologia 88(3): 507-508. 1996.

Common Name: none

Misapplied name: Tricholoma pessundatum

• Pileus

  Cap 5-12 cm broad, convex, expanding to nearly plane, often with a low umbo; margin inrolled, wavy, becoming decurved to nearly plane, frequently striate in age; surface viscid when moist, appressed fibrillose, brown to reddish-brown, darkest at the disc, slightly lighter at the margin; flesh thick, firm, pallid, unchanging; odor and taste farinaceous.

• Lamellae

  Gills adnexed, notched to arcuate, close, moderately broad, cream-colored, becoming pale-buff, the edges often developing brownish discolorations.

• Stipe

  Stipe 3-6 cm tall, 1-3.5 cm thick, stuffed to hollow at maturity, variable in shape: equal, narrowed to enlarged at the base, sometimes appearing clavate; surface pruinose or ridged from gill edges at the apex, cream-colored, elsewhere covered with appressed fibrils, buff-brown, discoloring darker brown from handling or in age; veil absent.

• Spores

  Spores 4.5-6 x 3-3.5 µm, elliptical, smooth, thin-walled, nonamyloid; spore print white.

• Habitat

  Scattered to gregarious under pines, especially Monterey Pine (Pinus radiata) and Bishop Pine (Pinus muricatum); fruiting from early to mid-winter.

• Edibility

  Possibly toxic.

• Comments

  For many years this Tricholoma was known as T. pessundatum, a European species. Kris Shanks has shown, however, that our local material has larger spores and a pileipellis that differs microscopically, thus worthy of species distinction. Tricholoma muricatum, is characterized by a brown to dark reddish-brown, viscid cap, the margin often striate at maturity, a strong, farinaceous odor, and gills that become mottled brown, especially the edges. It is most likely to be confused with Tricholoma fracticum, another dark reddish-brown, viscid species, but the latter forms a conspicuous dark annular line on the stipe, seldom has a striate margin, and lacks a strong farinacous odor. Another pine-dweller common in our area is Tricholoma imbricatum. It is similarly colored but can be distinguished by a dry, not visicd, fibrillose cap and usually mild odor.

• References

  Shanks, Kris M. (1994). A Sytematic Study of Tricholoma in California. Masters Thesis, San Franciso State University: San Francisco, CA. 207 p.
  Shanks, Kris M. (1996). New species of Tricholoma from California and Oregon. Mycologia 88: 497-508.
  Shanks, Kris M. (1997). The Agaricales (Gilled Fungi) of California. 11. Tricholomataceae II. Tricholoma. Mad River Press: Eureka, CA. 54 p.

• Other Descriptions and Photos
  • Fred Stevens: Tricholoma muricatum (CP)
  • Mushroom Observer: Tricholoma muricatum (CP)
  • Arora (1986): p. 185 (D), plate 35 (CP) [Tricholoma pessundatum]
  • Lincoff: p. 802 (D), plate 296 (CP) [Tricholoma pessundatum]
  • Smith & Weber: sp. 130 (D & CP) [Tricholoma pessundatum]
  
  

  (D=Description; I=Illustration; P=Photo; CP=Color Photo)