Major Groups > Boletes > Ridged/Pitted-Spored


Key to 11 Boletes with Ridged or Pitted Spores  

by Michael Kuo

These boletes are easy to distinguish, if you have a microscope, since they contain species with spores that are not smooth, which is unusual among boletes. In the genus Boletellus, the spores are ornamented with ridges, while spores in Austroboletus are finely pitted at maturity, and spores in Hemioporus are pitted or reticulate. Another bolete genus, Strobilomyces, includes species with spiny, reticulate spores, but Strobilomyces species are fairly easily separated from other boletes without using a microscope.

1.Stem shaggy, coarsely and conspicuously reticulate, or conspicuously ridged.

1.Stem fairly smooth, or finely reticulate.

2.Pore surface bruising blue.

2.Pore surface not bruising blue.

3.Stem and mature cap conspicuously scaly; growing terrestrially.
Boletellus fallax

3.Stem hairy and dotted, cap smooth becoming cracked; often (but not always) growing from or near rotting oak stumps.

4.Spore print olive to olive brown.

4.Spore print pinkish brown to reddish brown.

5.Cap smooth, moist to slimy when wet, shiny when dry; stem yellow, becoming reddish with age; spores pitted.

5.Cap velvety and dry; stem reddish brown, without a yellow stage; spores grooved and ridged.

6.Cap whitish to pale grayish yellow; taste bitter.

6.Cap reddish brown to brown; taste mild.
Austroboletus gracilis var. pulcherripes

7.Pore surface whitish at first, becoming pinkish to flesh-colored at maturity; stem usually graceful and slender.

7.Mature pore surface yellowish to bright yellow; stem variously shaped but not typically graceful and slender.

8.Cap pinkish to reddish, with very conspicuous, large, hairy scales; partial veil present when young.

8.Cap variously colored but not covered with large, conspicuous hairy scales; partial veil absent.

9.Cap blackish brown to brown, without reddish shades; often (but not always) growing from or near rotting oak stumps.

9.Cap reddish, at least when young; growing terrestrially.

10.Cap remaining reddish overall through maturity; taste acidic; most spores > 11 µ long.

10.Cap reddish when young but soon olive brown to olive gray; taste mild; most spores < 12 µ long.
Boletellus intermedius

(References used for this page can be found in the reference list for boletes.)

This site contains no information about the edibility or toxicity of mushrooms.

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Kuo, M. (2005, March). Key to 11 boletes with ridged or pitted spores. Retrieved from the MushroomExpert.Com Web site:

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