Which Bolete please ?

Monkeyd · #1 (**permalink**) 09-07-2011, 07:46 AM

Hi all,

I'm fairly certain these Boletes which appear on my front lawn each year at this time are of the same species.

But which one?

The nearest tree is a Cercidiphylum within a couple of meters.
Or a Cedar on my neighbours property on the otherside of their car park about 15 meters away.

I'm trying to expand on the Mycorrhizal species in a directory I'm putting together.

I'll be honest the Boletes & associates, give me a headache.

I don't have the capacity to look at spore in detail.

My thoughts are around;

B. subtomentosus
B. rubellus
B. versicolor

Any help greatly appreciated

David

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fairplay · #2 (**permalink**) 09-07-2011, 09:47 AM

Some good photos there Dave to work with, but is there any bluing of flesh or pores ? You do not appear to have cut or handled any - a MUST !

And what about when they first emerge, are they a lovely red colour which would tend towards rubellus ?

Hopefully someone would have the answer by the time I get back home, but I have to pop out now to have a look at a possible Sarcodontia crocea and bring a sample back - it's on old apple and ticks all the right boxes so hopefully, another new species for Suffolk.

Neil.

Andy Overall · #3 (**permalink**) 09-07-2011, 01:31 PM

These look like Xerocomus engelii, syn. with X. declivitatum and X. communis.

Andy

Monkeyd · #4 (**permalink**) 09-07-2011, 07:28 PM

Thanks to you both for the replies.

Niel, the emerging ones do not appear to have the deep red I would associate with B. rubellus (based on what i have seen in Id reference)

Also, a very good point on the staining, something I should of considered.
I will make a mental note.

Andy, I can not find reference to the specific Xerocomus species you list in any of my texts.
Phillips, Collins, Jordan, Keizer

Where can I find these?

Attached are a few extra shots.........

thanks D

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flaxton · #5 (**permalink**) 09-07-2011, 10:48 PM

David
There was a key published in Field Mycology, volume 9(3), 2008. The most recent was in Geoffrey Kibbys new book on Boletes.

Mal

Monkeyd · #6 (**permalink**) 10-07-2011, 06:11 AM

Thanks Mal,

will see if I can get access to one or both of those.

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Andy Overall · #7 (**permalink**) 10-07-2011, 09:20 AM

Hi David,

Yes unfortunately X. engelii does not appear in any books currently available. However, it is a species that is recognised in its own right by most mycologists. I say most because some believe it to be a form of X. rubellus. In my own experience X. rubellus is a beautiful red capped & stemmed species, the cap of which fades to a red brown with age. X. engelii is more variable in its always shade of brown be it pale or darker, sometimes with peach tones. Small red dots at the base of the stem (10x lens) when cut in section is supposed to be a good characteristic of X. engelii, however, I do believe that X. rubellus has these also. Some DNA work has been carried out on these small Boletes not least by British expert Alan Hills. This work has clearly defined the differences between some of these species but I'm not sure whether X. engelii is among those? I may well drop him a line and get the low down on this DNA work. I do know for a fact though that Alan considers X. engelii and X. rubellus separate species as does Geoffrey Kibby.

Andy

fairplay · #8 (**permalink**) 10-07-2011, 09:31 AM

I don't

(Sorry Andy, just winding you up !)

Neil.

Monkeyd · #9 (**permalink**) 10-07-2011, 05:39 PM

Quote:

Originally Posted by Andy Overall

Hi David,

Yes unfortunately X. engelii does not appear in any books currently available. However, it is a species that is recognised in its own right by most mycologists. I say most because some believe it to be a form of X. rubellus. In my own experience X. rubellus is a beautiful red capped & stemmed species, the cap of which fades to a red brown with age. X. engelii is more variable in its always shade of brown be it pale or darker, sometimes with peach tones. Small red dots at the base of the stem (10x lens) when cut in section is supposed to be a good characteristic of X. engelii, however, I do believe that X. rubellus has these also. Some DNA work has been carried out on these small Boletes not least by British expert Alan Hills. This work has clearly defined the differences between some of these species but I'm not sure whether X. engelii is among those? I may well drop him a line and get the low down on this DNA work. I do know for a fact though that Alan considers X. engelii and X. rubellus separate species as does Geoffrey Kibby.

Andy

thanks for the background Andy

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mollisia · #10 (**permalink**) 12-07-2011, 04:02 PM

Hello,

I also think that the shown fungus is Xerocomus clivitatum/communis/engelii.

I'm one of these who believe that rubellus and declivitatum are only varieties to each other and not species on there own. Why? Because both have the orange dots in the stipe base, which are lacking in all other Xerocomus species known so far. And they differ only in the pigmentation and may be in their ecology. But this may well be corelated and not two separate characters of their own. Additionally, the red pigment in Xerocomus is extremly variable. I have seen Xerocomus pruinatus entirely red, like X. rubellus. On the other hand I have seen collections of X. rubellus, were only very young fruitbodies showed red and the others were faded. So there is not much difference between declivitatum and rubellus in my eyes. But as I had no problems to tell them apart (when finding myself), I kept them as varieties in "Großpilze Baden-Württembergs".
What concerns the nomenclatorical odysee of this species, I'm not too sure why the new name was necessary, but I have not seen the publication about it yet. I think the taxon declivitatum MARTIN would be available and the description fits perfect. That the taxon communis is seen as nomen dubium is a good solution in my opinion.

best regards,
Andreas