Boletus amygdalinus (Thiers) Thiers
Calif. Mushrooms, p. 50. 1975.

Common Name: none

• Pileus

  Cap 4-10 cm broad, convex, broadly convex at maturity, margin often lobed or wavy, incurved when young; surface dry, at first chamois-like, then more or less glabrous in age, reddish-brown fading slightly at maturity; flesh thick, reddish beneath the cuticle, otherwise yellow, turning blue immediately when cut; odor and taste mild.

• Hymenophore

  Tubes depressed near stipe; pores rusty-red when young, becoming apricot-red at maturity, quickly bruising blue.

• Stipe

  Stipe 4-7 cm tall, 1.5-3.0 cm thick, equal to tapered to the base, solid; surface dry, reddish over a yellowish background, not reticulate, flesh yellow, quickly turning blue when cut.

• Spores

  Spores 11-14 x 5-6.5 µm, elliptical, smooth, conspicuously globulate (2-3 globules per spore); spore print olive-brown.

• Habitat

  Solitary to scattered under Liveoak (Quercus agrifolia) Madrone (Arbutus menziesii), and species of manzanita (Arctostaphylos); fruiting from late fall to mid-winter.

• Edibility

  Unknown, but many red-pored boletes are known to be at least mildly toxic.

• Comments

  Boletus amygdalinus is a handsome bolete distinguished by a reddish-brown cap, orange-red pores at maturity and rapid blueing of all parts of the fruiting body. Boletus erythropus is similar but has a darker, almost chocolate-brown cap and dark red pores at maturity.

• Other Descriptions and Photos
  • Nathan Wilson: Boletus amygdalinus (CP)
  • Nathan Wilson: Boletus amygdalinus (CP)
  • Michael Wood: Boletus amygdalinus (CP) -- very young sporocarp
  • Michael Wood: Boletus amygdalinus (CP) -- note the dark blue staining of the pores and stipe
  • Boletes of California: Boletus amygdalinus (D & CP)
  • Beverly Hackett: Boletus amygdalinus (I)
  • Beverly Hackett: Boletus amygdalinus (I)
  • Beverly Hackett: Boletus amygdalinus (I)
  • Michael W. Beug: Boletus amygdalinus (D & CP)
  • Robert Rich: Boletus amygdalinus (D & CP)
  • Bessette et al. (2000): p. 90 (D), p. 284 (CP)
  • Thiers (1975): p. 50 (D)

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