It has been a long time coming, but a paper by David Arora and Jonathan Frank that was published yesterday in North American Fungi makes the case that the red-capped king bolete of the southwestern USA deserves to be treated as a separate species from the familiar Boletus edulis of Europe, Asia, and elsewhere in North America.
Henceforth, assuming this taxonomy is not challenged, it will be known as Boletus rubriceps, of Latin derivation: rubr- (from ruber, L.) = “reddish”; ceps (L.) = “heads/caps”. This will also subsume another older provisional name for the species, B. “pinophilus”, which seems not to have been well accepted due to its differences from the European species of the same name, and should now be deprecated for our local red-capped beauty. Also note that B. luridus var. rubriceps is a distinct and only distantly related species.
By whatever name, it is my very favorite mushroom for the table, along with its cousin, B. barrowsii. I’ve collected it in Arizona and Colorado, and seen collections in the high conifer forests of Utah and New Mexico. I’m going back to the White Mountains this weekend for what will probably be the last flush of the season, following the rains earlier this week.
- ARORA, David; FRANK, Jonathan. Boletus rubriceps, a new species of porcini from the southwestern USA. North American Fungi, [S.l.], v. 9, p. 1-11, aug. 2014. ISSN 1937-786X.
Available at: <https://www.pnwfungi.org/index.php/pnwfungi/article/view/1267>.
Date accessed: 29 Aug. 2014. doi:10.2509/naf2014.009.006.
Note — 08-29-2014
Bill Warner has responded to this post today with some very erudite commentary that you’ll want to read if you take an interest in scientific taxonomy. He also enclosed a pic of Boletus luridus to show just how different it is from the new B. rubriceps.
Read your post on Boletus rubriceps today, and the taxonomist in me choked at seeing Arora describe a “rubriceps” given the priority of Boletus luridus var. rubriceps. But, the plant/fungus Code allows homonymy of infraspecific names (although there is a “recommendation” that one should not generate a homonymous infraspecific name in a genus where that name already is present as a valid species).
All of this simply leads to confusion, which is why we “more civilized” zoological taxonomists do not allow homonymy at any rank, and infrasubspecific taxa have no standing. When I saw your previous posts about B. luridus v. rubriceps, my immediate reaction was “NO WAY”–luridus is that red-pored poisonous one–and I rest my case about the plant code bubba-wisdom allowing homonymy! In any event, I am a bit surprised that Arora would create such a homynym, though, because if Boletus luridus var. rubriceps is ever elevated to specific status, Boletus rubriceps Arora & Frank becomes a specific homynym and because it is the newer name it would be dropped and again leave our local bolete without a valid name until a replacement is proposed!
Note that there are at least 5 different red-pored/blue-staining boletes in AZ (and most people incorrectly call all “Boletus satanus”) and they are normally considered poisonous. In checking into the “…var. rubriceps” it was interesting to see that Boletus luridus is eaten in Europe and some in the New World (and even considered “good”), even though it has been shown to contain at least some muscarine. Muscarine has the same anticholinesterase activity as the old organophosphate and carbamate pesticides (and military nerve gasses, Sarin, etc.!), although low levels usually don’t generate much in the way of symptoms unless one’s cholenesterase levels were already low because of medications, etc.
I collected a couple Boletus luridus on the way to the Foray (gave one to Chet for the show & tell). It immediately stained deep blue-black after cutting–check out the attached picture of the one from last Friday–that nearly black cut base had only been cut perhaps 2-3 minutes before! The species is very firm & heavy (like a good “former edulus” button)…maybe someday I will get up the nerve to try one. They are uncommon, but present along the Rim & Young roads, as is the also red-pored (but more maroon, like red velvet cake) and very probably poisonous Boletus haematinus–the most beautiful Arizona bolete in my opinion!