Observation 255268: Boletus gertrudiae Peck


collected for IGS

context slowly stains blue but not deeply

KOH turns bright RED

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Proposed Names

-31% (2)
Used references: B-R-B using key E-2 getting to couplet 8B and stalling
54% (6)
Recognized by sight

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Specimen accessioned to the University of Utah fungarium
By: Dan Molter (shroomydan)
2018-10-10 15:51:15 CDT (-0400)

This specimen has been accessioned to the UT fungarium with the following number:


By: I. G. Safonov (IGSafonov)
2018-04-11 18:48:34 CDT (-0400)

…Dr. Dentinger will sequence the ITS of this collection to compare with his earlier example of nobilis. My bet is that the sequences will match, especially given the fact that BD239 also originates from NC.
Despite the claimed inferior barcode gap for the LSU gene, I never had a problem successfully resolving bolete taxa with this locus. Importantly, LSU did a wonderful job resolving the true northeastern B. separans and its southeastern relative erroneously labeled as such in GenBank (one day it will be “now it can be told” story). The only case where it came close to not doing its job is that of “Xerocomus” sclerotiorum and its lookalike (e.g., 243879 and 215764) — the genetic distance is only 0.6%.

I wonder if ITS would help to differentiate this from BD239
By: Terri Clements/Donna Fulton (pinonbistro)
2018-04-11 18:01:02 CDT (-0400)

if they are in fact not conspecific. If ITS is a match to BD239 then that is what you have given the virtual LSU match. If ITS is not a match to BD239 then you can rule it out and you may pick up other matches to analyze. It looks like you have nothing to lose given the fact that your provisional morphological ID is not born out by molecular analysis as yet (of course the B. gertrudiae sequence may be mis-labeled which is another avenue that might have to be explored).

BD239 {edited}
By: I. G. Safonov (IGSafonov)
2018-04-10 17:04:18 CDT (-0400)

I don’t know what Dr. Dentinger’s collection looks like….
My current theory is that if Peck’s concept of nobilis matches the contemporary one, and there hasn’t been a concept drift over the years (a notion that was challenged by M. Kuo), it is possible that it’s synonymous with gertudiae. The fact that this obsie is perfectly contaxic with obs 255270 (a classic-looking nobilis?) vis-a-vis the matching sequences seems to support this hypothesis. By the way, the two collections were found very close to each other, as indicated by their pictures’ time stamps. This would also mean that GenBank’s AF457407 labeled as gertrudiae is something else, though all of these collections are “Alloboletus”.
For a curious case of B. gertrudiae, which was described twice, see my commentary in http://mushroomobserver.org/name/show_name/19414.

Out of curiosity
By: Terri Clements/Donna Fulton (pinonbistro)
2018-04-10 16:41:15 CDT (-0400)

what does Dr. Dentinger currently call his voucher BD239, the only one labeled Boletus nobilis on GenBank, the LSU of which is a virtual match with this obs.? I noticed he retained the name from initial publication of EU232002 in 2010 to HQ161813 in late 2016. A total of five sequences were published for this voucher including LSU, ITS, RBP1 and others excepting TEF. It is a 99.9% match with this obs whereas the match with B. gertrudiae is only 98.5%.

This collection…
By: I. G. Safonov (IGSafonov)
2018-04-10 16:12:48 CDT (-0400)

…was sent to Dr. B.T.M. Dentinger at UMNH in March 2018.

Yes, Geoff,
By: I. G. Safonov (IGSafonov)
2017-11-22 13:11:34 CST (-0500)

I am working on it, but this “Alloboletus” business is getting a bit messy and complicated for my taste. :-) Sure, all of this is a lot of fun, and I like the challenge, yet I am beginning to wonder if I am biting more than I can chew. :-)

After doing some additional literature research, I’ve decided to remove my nobilis proposal from this observation. Also, I’ve just edited by last comment to reflect my new ideas expressed below.

Here is the evidence I am currently considering:
1) This collection of your (255268) is a dead ringer for gertrudiae, as we now know it AND, more importantly, as Peck originally described it (see Peck description in Smith & Thiers at https://quod.lib.umich.edu/...).
2) Smith & Thiers (1971) thought B. nobilis Peck and their concept of B. separans were conspecific. In other words, they thought Peck had described the same species twice. However, Ernst Both in his Bolete Compendium (1993) writes that R. Singer disagreed with them and that in Singer’s opinion their concept of separans had been based on Peck’s nobilis! M. Kuo, too, in his nobilis pages opines that Smith & Thiers were wrong about making B. nobilis and B. separans conspecific, though he doesn’t say how this hypothesis originated. At the same time, the black-and-white picture of B. separans in Smith & Thiers’ The Boletes of Michigan (Pl. 118 right side, collection Smith 75783) shows a young fruitbody with a finely corrugated dark cap and generally dark reticulation on white or pallid stipe. IMO this collection fits the modern concept of separans better than it does the modern concept of nobilis.

Sooo… When you distill down this mess, including the implications of the sequencing data of your 255268 & 255270, the following alternative hypothesis can be proposed:
1) Maybe Smith & Thiers were right in that Peck’s nobilis = Peck’s separans. Moreover, Kuo challenges the current concept of nobilis vis-à-vis Peck’s nobilis. This leaves B. nobilis a questionable name – nomen dubium – and possibly makes it a phantom taxon.
2) On the other hand, Peck’s B. gertrudiae appears to be a legit and real species that exists in two (or more) morpho-forms represented by your vouchers that are genetically conspecific. Then, at least some entities of what we’ve been calling nobilis in the sense of contemporary authors are actually B. gertrudiae Peck. The latter notion is, too, supported by the LSU and TEF-1 data of your two collections, Geoff.
3) I suspect there are additional cryptic “Alloboletus” species that fit the current concept of “nobilis” and masquerade as look-alikes of your "nobilis-like gertrudiae”/obs 255270. For example your other collection (obs 254370) supports the presence of additional, unrecognized taxa of NA “Alloboletus”.

Obviously, sequencing of additional vouchers of members of “Alloboletus” from a wider geographic range in the northeast will be necessary to anchor appropriate species epithets and delineate and circumscribe all suspected morpho-species and morpho-forms.

You may be the one
By: Geoff Balme (geoff balme)
2017-11-21 12:50:31 CST (-0500)

TO put some solution on this! Thanks for the link to the Kuo article. I wonder if we’ll ever get this sorted out. That discussion of the various authors misunderstanding and being vague reminds a lot of the work I did on the leafhoppers where it was nary impossible to get a good consensus on the concepts of what the species were. And of course the DNA/RNA markers helped not at all. :(

Anyway! This is fascinating fun!

Geoff, [edited XI-22-27]
By: I. G. Safonov (IGSafonov)
2017-11-21 09:05:58 CST (-0500)

The only “confirmed nobilis” is Peck’s holotype. I am not sure what we can do with Peck’s type material from the molecular perspective though (too old for sequencing). See the “nobilis conundrum” M. Kuo is talking at http://www.mushroomexpert.com/boletus_nobilis.html.
I think the sequencing data gives an interesting insight into what the modern species concept for this entity should be, though it’s just a few scattered data points so far. Still, based on these data and M. Kuo’s commentary, I am beginning to wonder if at least some collections of nobilis (in the sense of modern authors) and gertrudiae posted to MO and elsewhere are conspecific. This also begs a question of whether nobilis Peck is a legit taxon in light of the doubts expressed by Smith & Thiers in The Boletes of Michigan (they thought it was conspecific with their concept of B. separans).
I have another collection of suspected gertrudiae in my herbarium. That one I think is from Dario Z. from VA. I might as well sequence it, too, just in case.

well variation in form
By: Geoff Balme (geoff balme)
2017-11-21 08:30:21 CST (-0500)

fits with my original concept of these things. It’ll be very nice when someone gets a confirmed nobilis on the dock. :)

TEF-1-alpha sequencing discussion
By: I. G. Safonov (IGSafonov)
2017-11-20 22:48:34 CST (-0500)

> A clean and contiguous TEF-1 sequenced of 614 bps was obtained from this material and posted to the comment below. There are no ambiguous characters.
> As expected, a BLAST search of this sequence gave a hit list consistent with this being a member of the “Alloboletus” lineage of Boletus sect. Boletus (aka Boletus sensu stricto). There are no perfect or close matches, as TEF-1 for nobilis is not in GenBank yet! The top 5 hits with ~96—>93% similarity are vouchers of Boletus violaceoufuscus (2), Boletus separans, Boletus semigasteroides (=Notholepiota areolata), and Boletus sp. HKAS62903. Then there is a sudden drop off to 89% with B. reticuloceps, a core member of porcini s.s.
> This sequence is also a 100% match to that of Geoff’s Boletus nobilis of obs 255270.
> The only conclusion one can make on the basis of this sequencing effort (both nrLSU & TEF-1) is that 255268 is perfectly conspecific with 255270. In other words, genetically this collection, too, is Boletus nobilis, barring any errors in specimen handling.

nrLSU Sequencing Results & Discussion
By: I. G. Safonov (IGSafonov)
2017-05-06 19:21:21 CDT (-0400)

> A clean and contiguous nrLSU sequence of 980 bps was obtained from this collection. There are no ambiguous characters.
> A GenBank BLASTn search of the whole sequence gave the following hit profile (sorted by identity):
Top hit: EU232002 = Boletus nobilis voucher BD239 (MIN) = 843/844 = 99.9% similar (1 gap)
Hit #2: AF457407 = Boletus gertrudiae = 881/894 = 98.5% similar (w/ 5 gaps)
Hit #3: JN563860 = Boletus violaceofuscus strain HKAS-62901 = 909/924 = 98.4% similar (w/ 2 gaps)
Hit #4: JN563859 = Boletus violaceofuscus strain HKAS-62900 = 903/920 = ~98.2% similar (w/ 3 gaps)
Hit #5 = AF457403 = Boletus violaceofuscus = 871/892 = 97.5% similar (w/ 7 gaps)
Hit #6: KF030329 = Boletus separans voucher DPL2704 = 871/893 = 97.5% match (w/ 7 gaps)
Hit #7: EU232000 = Xanthoconium separans voucher BD243 (MIN) = 822/844 = 97.4% similar (w/ 7 gaps)
Hit #8 = AF457404 = Boletus separans = 864/893 = ~96.8% similar (w/ 9 gaps)
Discussion: B. gertrudiae, B. nobilis and B. separans are the three iconic and legitimate North American taxa. Phylogenetically they belong to the ‘Alloboletus’ section of the porcini sensu lato clade (=Boletus s.s.). They have solid and unambiguous species concepts that, by and large, allow their separation in the field. However, older, bleached out specimens of separans can be confused with those of nobilis and M. Kuo discusses this point as well as the inconsistencies in the modern species concept of the latter taxon vis-a-vis Peck’s original description (http://www.mushroomexpert.com/boletus_nobilis.html). Of the three, B. gertrudiae is the most distinct and less frequently encountered entity, but its confusion with B. nobilis has also been documented (e.g., Bill Yule’s obs 49526). The bottom line is that IMO 255268 is a good phenotypic (morphological) match for B. gertrudiae.
Macro-morphology, phenotypes, and morpho-species concepts aside, the genetic evidence in hand needs to be made sense of and reconciled with what’s seen by the naked eye and with the GenBank records. The LSU trace of 255268 is a perfect match to those of GenBank’s Boletus nobilis EU232002 and of Geoff’s obs 255270. Now, since 255270 fits the current species concept of B. nobilis and we can now tie this phenotype with the LSU genotype, does this mean that 255268 is also nobilis, even though the morphology instead implies gertrudiae? What about both nobilis and gertrudiae possibly having identical LSU sequences because they are very closely related, just like it seems to be the case with several red-pored boletes I had recently sequenced? And what about Geoff’s obs 254730 that doesn’t look like separans at all, yet having its LSU perfectly match GB’s records of separans, KF030329 and EU232000 (hits Nos. 6 & 7 above)?
Unfortunately, none of these theories can be proved or disproved with confidence till other loci (preferably TEF-1 or RPB1/2) of these and other reliably identified collections of North American members of ‘Alloboletus’ are sequenced and aligned.
For now, despite the genetic evidence to the contrary, I will maintain that 255268 is Boletus gertrudiae.

I would not have
By: Geoff Balme (geoff balme)
2016-10-06 08:30:35 CDT (-0400)

picked the key to get to B. gertrudiae which is a net stipe key — I did not see a reticulation on this stem, or at least I didn’t think so. I think I’ve got a long way to go before I can begin to trust my keying. As I said above I used E-2 and the only yellow one in the 8B couplet was the one I selected. Booo.

I agree, I was only guessing
By: Geoff Balme (geoff balme)
2016-10-05 22:04:49 CDT (-0400)

and of course with a little help B. gertrudiae looks a good fit!

Yellow coloration
By: Phil Yeager (gunchky)
2016-10-05 21:29:20 CDT (-0400)

at stipe apex supports B. gertrudiae.

Thank you…
By: I. G. Safonov (IGSafonov)
2016-10-05 21:18:46 CDT (-0400)

…very much, Geoff, for collecting these for me. How did you come up with B. melleoluteus? Looking at the description of this species in NAB/BRB and also Both’s Bolete Compendium, I don’t think it’s that one. I must agree that B. gertrudiae is a much better proposal.

Reminds me of what I saw
By: Christian (Christian Schwarz)
2016-10-05 18:24:24 CDT (-0400)

called B. gertrudiae, but I forget what Noah found out about the staining / KOH reactions of that species

I’m taking a guess!
By: Geoff Balme (geoff balme)
2016-10-05 17:25:12 CDT (-0400)

I’m not sure! I’m hoping some folks jump in here. I hate to post without a guess.

By: Eva Skific (Evica)
2016-10-05 17:24:05 CDT (-0400)