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Observation 462750: Xerocomoideae Singer

When: 2021-07-22

Collection location: Tamworth, New Hampshire, USA [Click for map]

Who: Chris Neefus (Chris Neefus)

Specimen available
Collection number: Chris Neefus CDN2196

Habitat: Hemlock forest
Substrate: duff
Abundance: Quite a Few


Spores 14.4 × 4.4 uM
in KOH

Proposed Names

28% (1)
Recognized by sight: Kinda looks like it + hemlock associate
Based on chemical features: 1) ITS sequence & BLASTn results
2) B. miniato-olivaceus is a member of Xerocomoideae (based on LSU & TEF-1 data), possibly a member of Pulchoboletus or a sister genus
16% (2)
Based on chemical features: The ITS sequence matches that of a collection from Yves Lamoureux that he named B. miniatopallescens.
56% (1)
Based on chemical features: ITS sequence places it there. Likely not a Pulchroboletus but in a new sister genus together with Boletus miniato-olivaceus and the western Boletus smithii

Please login to propose your own names and vote on existing names.

= Observer’s choice
= Current consensus


Add Comment
Hello, Renée
By: I. G. Safonov (IGSafonov)
2021-08-05 20:53:25 +04 (+0400)

Thank you for chiming in. Please see obs 280028 for more info on ?? B. miniato-olivaceus. Your sequenced collection appears to be clading in ??Butyriboletus by ITS. I don’t think I am familiar with your bolete. It also looks different from the concept of miniato-olivaceus presented by numerous observations on MO, most of which have been correctly identified, IMO:

Let’s hope that the sequencing work done on Quebec Boletes by Stefani (not Mycoquébec)
By: Renée Lebeuf (Renée Lebeuf)
2021-08-05 19:09:58 +04 (+0400)

will help shed some light on these poorly known and rare species in the province. I also have a collection with a different ITS, collected under beech, that I renamed B. miniato-olivaceus after seeing fresh specimens in Maine. GB accession # KY826199.1

By: Robert(the 3 foragers) (the3foragers)
2021-08-04 01:08:46 +04 (+0400)

that is interesting.

By: I. G. Safonov (IGSafonov)
2021-08-03 20:05:31 +04 (+0400)

Chris, can you make the last photo showing the intact mushrooms the thumbnail picture?

More info
By: I. G. Safonov (IGSafonov)
2021-08-03 20:02:30 +04 (+0400)

See Boletus roodyi,, for which I got ITS, LSU & TEF-1. The distance and ML trees for TEF-1 place it in Xerocomoidea, but it belongs in its own genus. The same trees show that B. miniato-olivaceus is unlikely to be a member of Pulchroboletus.

By: I. G. Safonov (IGSafonov)
2021-08-03 19:50:42 +04 (+0400)

Yes, MycoQuebec has it backwards. :-) I am not sure how they mixed these two species up, considering that the concept of miniato-olivaceus has been elucidated a long time ago. While I am not surprised they missed Roy Halling’s publication on this subject, Bessettes’ field guides (2001 & 2016) have the right concept of this bolete (including the photos).
Smith’s holotype of B. miniato-pallescens is exactly 86 years old. Depending on how it was stored, it could still have enough intact DNA to yield an ITS sequence via NextGen methodology. Dr. Timothy James is your contact at MICH. I think you would have no trouble getting the type on loan or at least getting a sample for sequencing because you are a member of the academia.
I am not aware of anyone working on these these two species, but then I am hardly the person who can answer this kind of question anyway. :-)

MycoQuebec has it backwards as well.
By: Chris Neefus (Chris Neefus)
2021-08-03 16:56:56 +04 (+0400)

Under B. miniato-olivaceus, MycoQuebec list:
“Ecology – mycorrhizal on soils of deciduous or mixed forests, often with beech trees” and goes on to say “Boletus miniatopallescens is much more tomentose and grows under hemlock trees”. Interestingly, Y. Lemouroux wrote that the specimens that he has identified as B. minipallescens were collected under hemlock. According to Renee these are the specimens with ITS sequence on GenBank that match my observations from Tamworth NH. It appears that folks have differing concepts of the the 2 species, and, as you suggest, it may be a species complex. I suppose that if Smith and Theirs holotype is available, it might not be too old to sequence. Do you know if anyone is formally working on a revision of the family that they plan to publish?

Thank you, Chris
By: I. G. Safonov (IGSafonov)
2021-08-03 04:04:23 +04 (+0400)

Getting TEF-1 of this collection and/or obs 325536 sequenced would be very helpful to compare with obs 320058 from CT that has been identified as Boletus miniato-olivaceus.
I am prepared to sequence my own collection of B. miniato-olivaceus from NJ, obs 280028, but, unfortunately, I will have to wait months for this to happen. [By the way, that observation features Roy Halling’s clarified morphological concept of miniato-olivaceus.] Alternatively, I can as Dave W for one of his vouchers of this taxon, which is fairly common in the hemlock woods in his area.

I think you have it backwards… [edited]
By: I. G. Safonov (IGSafonov)
2021-08-03 03:35:50 +04 (+0400)

It’s miniato-olivaceus that is associated with the hemlock, while miniato-pallescens is a hardwood associated species. Read Smith & Thiers’ description of the latter taxon in their book.
My current concept of miniato-pallescens is represented by the following observations: obs 215764 (ITS, LSU & TEF-1), obs 244588 (ITS & LSU), obs 286328 (TEF-1), obs 331470 (ITS), obs 429232 (to be sequenced, same site as MO286328), obs 431713 and obs 461524. It’s actually a sister taxon to Pulchroboletus sclerotiorum by DNA. I cannot really prove it to be “mini-p” because Smith’s type hasn’t been sequenced.
I think your bolete could be a third species that is different from miniato-olivaceus and the cryptic Pulchroboletus/suspected minato-pallescens above. While I don’t have the ITS of presumed miniato-olivaceus collections sequenced, it could be different from yours. This is something I need to look into using the material from my herbarium or from Dave W’s in PA.
By the way, you made an earlier collection of this interesting bolete, obs 325536, which is conspecific with the present post by ITS. The ITS is different from MO331470 above and the staining of the flesh is minimal, just like in the present obsie.

I’ll sequence TEF1
By: Chris Neefus (Chris Neefus)
2021-08-03 03:30:59 +04 (+0400)

I’ll sequence TEF1 later this week to see if it matches Igor’s B. minio sequence. Clearly the ITS sequence didn’t match the GB B. minipallescence sequences.

ITS sequence matches specimens the Yves Lamoureux identified as B. miniatopallescens
By: Chris Neefus (Chris Neefus)
2021-08-03 02:46:05 +04 (+0400)

According to Renee Lebeuf, the ITS sequences that this matches were from specimens that Yves Lamoureux identified as B. miniatopallescens. Apparently it is extremely rare in Quebec, having been collected only 3 times in the same time period in 2004. According to Y. Lemoureux, the association with hemlock is one character that distinguishes it from B. miniato-olivaceus.

Canadian accessions
By: I. G. Safonov (IGSafonov)
2021-08-02 06:06:18 +04 (+0400)

If you contact Renee Lebeuf via email, she will likely be able to tell you you what those matching hits are. I’ve done this myself many a time to get ID confirmations from Renee for my own collections/sequences that matched Canadian sequences. MycoQuebec folks did ID most of their collections, but for some reason chose not to apply any names to their older accessions in GenBank.

Possibly so.
By: Chris Neefus (Chris Neefus)
2021-08-01 05:52:36 +04 (+0400)

B. miniato-O was my first impression but when blast did return a match I wasn’t confident. I didn’t check to see if there were any B miniato-olivaceus ITS sequence on GenBank. It does match a couple of sequences from Canadian specimens but they haven’t put a name on them.