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When: 2008-10-17

Collection location: Forest near Elgin St., Pembroke, Ontario, Canada [Click for map]

Who: Paul Derbyshire (Twizzler)

No specimen available

This sizable bolete was growing under jack pine.

It looks like it’s one of the boletes more closely related to the gilled genus Paxillus, from its general shape and other features.

Species Lists


Proposed Names

-50% (5)
Used references: Aurora’s Mushrooms Demystified. Keys out to B. affinis, although not previously known from Canada. Usually associated with pine in Southeastern U.S. according to Aurora. It also could be a species novum. That red-striated stipe is sure distinctive, and I can find nothing matching it.
-38% (5)
Recognized by sight
34% (5)
Recognized by sight
49% (5)
Recognized by sight

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

= Observer’s choice
= Current consensus


Add Comment
Just wondering
By: Dave W (Dave W)
2010-02-22 18:25:31 CET (+0100)

whether this specimen exhibits some trait not recognizable within the species heading “Boletus subtomentosus” as used in many NA manuals. Or is the heading “Boletus sp” better to use because the use of “subtomentosus” is not well understood… at least not in NA. As described in Phillips, this specimen does appear to fit in with subtomentosus.

Errr, someone still has a positve vote for it.
By: Jason Hollinger (jason)
2010-02-19 16:10:44 CET (+0100)

Screwy as it looks, it’s only looking at the highest vote you give the two, it should have no effect on the outcome.

I am going to fix this silly problem that not even an admin is allowed to delete names that have a positive vote. I grow weary of that “feature”…

Can you at least fix the observation?
By: Paul Derbyshire (Twizzler)
2010-02-19 09:07:32 CET (+0100)

E.g. delete the second B. affinis naming (for some reason I can’t seem to).

Double-naming mystery explained
By: Jason Hollinger (jason)
2010-02-19 05:32:15 CET (+0100)

It looks like Tuberale originally proposed Boletuss affinis, then Twizzler proposed Boletus affinis. Later someone merged the misspelling into the correct name, leaving two identical namings for the same observation. The RSS log shows the full history:

Good to know it’s not a bug in my code! :) Well… it sort of is, because this isn’t ideal behavior, but it is at least understandable. And there’s no plans to fix it!

According to Kuo
By: Dave W (Dave W)
2010-02-18 19:50:09 CET (+0100)

one gets different reactions for X. affine and B. subtomentosus when ammonia is applied to the cap surface. In my mind I don’t recall an association of X. affine with any of the poplars. Phillips lists oak and beech as the primary associates, which basically agrees with my experience. One manual (forget which one… it’s at home) draws a parallel between B. subtomentosus and the so called “Gilled Boletes”… (forget the genus name at the moment).

There is
By: Paul Derbyshire (Twizzler)
2010-02-18 19:07:39 CET (+0100)

quaking aspen (Populus tremuloides) in the same area.

Thanks Noah.
By: Dave W (Dave W)
2010-02-18 17:12:37 CET (+0100)

I agree about the pore size seeming a bit large for the affine types. (Not sure if maybe a very mature one might have enlarged pores.) I have seen (what I IDed as) affine with aerolate cap. Although some boletes seem more likely to develop the cracks, I have seen examples of many different types where the cuticle breaks up… probably due to weather conditions. Just checked MushroomExpert, and Kuo’s examples of subtomentosus do show the reddish/brownish vertical steaks on the stalk… like this example (12890). Xanthoconium affine types also tend to show the vertically streaked stalks. But I think I’d lean toward the subtomentiosus… partly due to habitat.

pore surface
By: Noah Siegel (Noah)
2010-02-18 14:06:31 CET (+0100)

is to yellow for X. affine and the pores look to big. The areolate cracking of the cap also doesn’t fit. This is something like Boletus subtomentosus

By: Dave W (Dave W)
2010-02-18 13:47:17 CET (+0100)

It seems clear that Twizzler made the initial proposal, as he is the collector. An interesting question is… Why the discrepancy in community ratings for the same proposed IDs? And yet another question… Why a negative rating without some relevant reason posted. Personally, I think that it is good form to post a few relevant details when a “no way” or “I doubt it” vote is cast…. Just my opinion.

This one looks like one of the affinis types to me. I find lots of these here in PA… but I don’t recall ever finding any under pine. Oak, beech and other deciduous trees are the typical hosts.

This is odd.
By: Paul Derbyshire (Twizzler)
2010-02-18 06:52:28 CET (+0100)

How did this observation end up with two of the same name proposed, with different proposers and votes?