Observation 168223: Boletus fairchildianus (Singer) Singer

When: 2014-06-23

Collection location: Buncombe Co., North Carolina, USA [Click for map]


Who: Mike Hopping (AvlMike)

No specimen available

Found in mixed hardwoods. No pink remaining on cap of this mature specimen. Sterile margin present. Upper stipe bright yellow with raised red scabers. Flesh pale yellow, instantly staining blue. All other parts instantly staining blue as well. Pores orange at stipe, transitioning to yellow at margin.

I think this would have been B. rubricitrinus var. fairchildianus—a species MycoBank has changed to B. fairchildianus. Alternatively, Index Fungorum appears to have done away with B. rubricitrinus altogether, subsuming it into B. fairchildianus (Singer) Singer.


Boletus rubricitrinus 2.jpg

Proposed Names

54% (1)
Eye3 Eyes3
Used references: North American Boletes, Index Fungorum, MycoBank
Based on chemical features: NH4OH on pileipellis=green, KOH on pileipellis=maroon

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Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
the discolor group
By: Mike Hopping (AvlMike)
2014-06-25 07:53:41 MST (-0700)

The characteristics of B. rubricitrinus, B. fairchildianus and B. discolor seem like small color variations on a theme. They share raised red dots on the stipe, instant bluing all over, and pileus reactions to NH4OH and KOH. Does your concept of “the discolor group” include these other species?

I didn’t do FeSO4 testing—one day I’ll learn that just because a test isn’t mentioned for a species in my keys doesn’t mean it doesn’t count. But I can say, though it’s not obvious in the picture, that there was no darkening of the disc in this specimen. And the raised red dots were more prominent than they appear. FWIW

By: Noah Siegel (Noah)
2014-06-25 06:24:02 MST (-0700)

looks to be in the B. discolor group.

Index Fungorum correction
By: Mike Hopping (AvlMike)
2014-06-25 05:38:34 MST (-0700)

When the Bessettes learned that B. rubricitrinus had been downgraded to a synonym by Index Fungorum, they decided to investigate. I’ve now received word from them that the change has been acknowledged as mistaken and will be corrected. B. rubricitrinus remains the accepted name for the yellow-pored form of the mushroom. B. fairchildianus is the accepted name for the form with red pores.

So, does orange count as red?

Created: 2014-06-23 13:33:40 MST (-0700)
Last modified: 2014-06-24 13:49:13 MST (-0700)
Viewed: 115 times, last viewed: 2018-05-16 07:49:52 MST (-0700)
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