Boletus chrysenteron Bull.
Fl. mycol. France: 418. 1888.

Common Name: none

Synonym: Xerocomus chrysenteron (Bull.) Quélet

• Pileus

  Cap 4-9 cm broad, convex, becoming nearly plane in age; surface dry, tomentose, dark brown to olive brown, soon areolate, the exposed context pallid at the disc, pinkish near the margin; flesh white, thick, sometimes blueing when bruised; odor mild, taste acidic.

• Hymenophore

  Pores relatively large, 1-2 mm, yellow, olive-brown in age, typically bruising blue.

• Stipe

  Stipe 5-10 cm tall, 1.0-1.5 cm thick, dry, smooth to longitudinally ridged, yellowish, with reddish tints usually predominating at the base.

• Spores

  Spores 11.5-14.0 x 4-6 µm, smooth, elliptical to fusiform; spore print olive-brown.

• Habitat

  Solitary or in small groups in hardwood/conifer woods from early fall to mid-winter.

• Edibility

  Edible, of fair quality.

• Comments

  This drab member of the Boletus clan is recognized by a dark brown-brown to olive-brown areolate cap, and slow, not always consistent blueing of the tubes and cut flesh. Boletus truncatus is a closely related species which cannot be reliably told apart without a microscope although cracks in the cap context tend not to turn pink as in B. chrysenteron. To confirm an identification requires an examination of spores. In Boletus truncatus, as the name suggests, the spores are either blunt or truncate at one end, while in B. chrysenteron they are rounded. Another related species is Boletus zelleri, but it has a darker, less cracked cap at maturity, and a more uniformly red stipe.

• References

  Ladurner, H. & Simonini, G. (2003). Xerocomus s.l. Edizioni Candusso: Alassio. 527 p.
  Smith, A.H. & Thiers, H.D. (1971). The Boletes of Michigan. University of Michigan Press: Ann Arbor, MI. 426 p.
  Thiers, H. D. (1975). California Mushrooms—A Field Guide to the Boletes. Hafner Press: New York, NY. 261 p. (WWW)

• Other Descriptions and Photos
  • Taylor F. Lockwood: Boletus chrysenteron (CP)
  • Taylor F. Lockwood: Boletus chrysenteron (CP) -- closeup of pileus
  • Michael Wood: Boletus chrysenteron (CP)
  • Michael Wood: Boletus chrysenteron (CP)
  • Michael Wood: Boletus chrysenteron (CP)
  • Boletes of California: Boletus chrysenteron (D & CP)
  • Beverly Hackett: Boletus chrysenteron (I)
  • Boleslaw Kuznik -- Hunting for Mushrooms: Boletus chrysenteron (CP)
  • Na Grzyby: Boletus chrysenteron (D & CP)
  • Pilze, Pilze, Pilze: Xerocomus chrysenteron (CP)
  • Arora (1986): p. 519 (D & P)
  • Bessette et al. (2000): p. 104 (D), p. 288 (CP)
  • Breitenbach & Kränzlin (vol.3): sp. 56 (D, I, & CP) [as Xerocomus chrysenteron]
  • Jordan: p. 344 (D & CP) [as Xerocomus chrysenteron]
  • Lincoff: p.567 (D), plate 423 (CP)
  • McKenny et al.: p. 3 (D), p. 2 (CP)
  • Miller: sp. 313 (D & CP)
  • Phillips: p. 216 (D), p. 217 (CP)
  • Smith & Weber: sp. 84 (D & CP)
  • Thiers (1975): p. 79 (D)
  
  

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