Part of the US Forest Service 2011-2013 Southern Cascades Fungi Survey.
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Daniel Nicholson, US Forest Service

Proposed Names

93% (3)
Used references: Clarifying the butter Boletes: a new genus, Butyriboletus, is established to
accommodate Boletus sect. Appendiculati, and six new species are described
David Arora and Jonathan Frank
Based on microscopic features: Spring montane fruiting, vinaceous-red cap, yellow pores that stain blue.

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= Observer’s choice
= Current consensus


Add Comment
Jonathon Frank, right?
By: Debbie Viess (amanitarita)
2014-01-03 14:24:12 CST (-0500)

Lotsa cryptic species within the butter bolete complex here in the west. And some of these publications take forever to get to light…

It’s been a work in progress for several years now. Patience. ;)

Daniel, is the “no herbarium specimen” an oversight?

What are the salient characteristics for this particular butter, that separates it out from the rest?


currently in publication and will get a (three) new name(s) shortly.

Why is this still unnamed?
By: Gerhard Koller (Gerhard)
2014-01-03 14:00:46 CST (-0500)

Is it that difficult to give this conspicuous bolete a new name? Every tiny fungus has a proper name! You named all your cejps with proper names by now, e.g. B. regineus …. why not this royal American Bolete? I do not get it.