Bolete

[SheffieldLass]

Thanks (and congratulations on finding it and getting an id for it)

Doesn't really make it any easier here ... our tree species are too mixed. Pine next to beech next to oak next to other conifers.

Those dark ones I found the other day did have a reddish brown stem with brownish reticulum and they were near a mature oak. I hadn't got my camera when I saw them. My computer was full to explode, and my camera card also full, so didn't seem any point in taking my camera with me . Went back yesterday to see if any more had appeared, but sadly no. Boletus edulis about 2m away though .... And I've got a new external hard drive with 2tb space, so now room for more photos

Melanie

[Chris Yeates]

Originally Posted by flaxton

Confirmed as B aereus

Mal

excellent Mal - new to Yorkshire (and with solid provenance/expert confirmation)

keep 'em coming

Chris

[SheffieldLass]

Can you post a pic of a close up of the stem to see the reticulation?

One of my dark ones was through today, with a very happy slug feasting on it ... Whadyerthink? The flesh didn't stain red with ammonia, so not B pinophilus, and no pines at that spot anyway.




It isn't B edulis. The caps on these are always dry and wrinkled, not greasy. And the maggots don't go for them either. They know the difference.

Must also find the post of one of mine from last year, different spot in the forest though.

Melanie

[SheffieldLass]

Found a nice picture on WAB of B aereus which shows the reticulation nicely. Very dark brown at the top. Mine isn't that colour. Mine is much paler ....



Melanie

[SheffieldLass]

This was the one of mine from last year.

More Boletes for id

Melanie

Just looked back through my photos and this shows the stipe much more clearly. paler reticulation at the bottom, but does seem concolorous with the stipe higher up. I know that spot is mainly purple beech but there may well be the odd oak amongst them. It's only 10 minutes walk up the road so easy to check that ....

[flaxton]

Melanie

Even this photo shows the reticulations as lighter than they actually were (they were almost concolourous) but it gives a good idea of how dark it was.


A second fruit-body was growing alongside and had a much thicker (and I think more usual) stipe but unfortunately that was wrapped round the wire fence it was growing through.

Your photo definitely looks non-edulis like. Lets see what Andy thinks.

Mal

[Andy Overall]

Mmmmm those stem colourations can really differ as can the definition of the reticulation. The picture that Melanie put up of B. aureus does looks different to B. edulis, but the picture of her own looks more like B. edulis to me, the white margin helps. I collected something the other day that I was conflicting over, B. reticulatus or B. edulis? it had characteristics of both. I came to a decision only when I had taken a look at the cap cuticle hyphae, swollen ends with B. reticulatus not with B. edulis. Its that close between them. Has DNA been done on any of these??????

Andy

[Chris Yeates]

Originally Posted by Andy Overall

. . . . Has DNA been done on any of these??????

Andy

what on an economically important group like this? you bet!

here is a sample from A Phylogenetic Study of Boletus section Boletus in Europe in Persoonia (2008) 20, pp. 1-7:

"Phylogenetic analysis of the ITS and GAPdH and the ITS sequences including the samples of Leonaridi et al. (2005) consistently produced the same four clades. These clades are:
1. A clade containing a large number of samples identified as being B. betulicola, B. edulis, B. edulis var. albus, B. edulis var. pusteriensis, B. quercicola, B. venturii and morphotaxa A, B, C;
2. B. pinophilus;
3. B. aereus; and
4. B. reticulatus.

There is no resolution within the B. edulis group. All the clades are well to moderately supported using bootstrap and posterior probabilities. Within the B. edulis clade, almost no genetic variation was observed, though many distinguishable morphotypes were included plus a wide geographic sampling. Within each group no differences has been found between Northern Europe and Southern Europe B. edulis, B. reticulatus and B. pinophilus. Our molecular results and those of Leonardi et al. (2005) indicate that within the B. edulis clade there is little genetic variation,
even for a marker often used in species level distinction in the fungi. The ITS is commonly used for many organisms and is useful for separating species in Basidiomycetes. For example, Hughes et al. (1999) used ITS sequences to distinguish species of the genus Flammulina and Kretzer et al. (1996) used ITS for recognizing different species in the genus Suillus s.l. But the ITS region also has limitations. According to Bruns (2001), there is often little genetic variation among very closely related species. To corroborate the results of the ITS data, we used an additional section of dNA (GAPdH) as this region was useful in distinguishing species of the genus Leccinum (den Bakker 2004b). Very little genetic differences were also found using the GAPdH dataset. The assignment of different putative species, for specimens that show slight morphological variation or different host plants, cannot be supported by our genetic data suggesting that they are all one species.
A collection with a purely white fruit body, often referred to as B. persoonii in the literature, appeared to be similar to B. edulis in morphology, and must therefore be considered a mere white
form of that species, for which the name B. edulis var. albus is available. Three morphotaxa, which could be distinguished from B. edulis in the morphological study of Van der Linde (2004), did not get support from the molecular data and must be considered to fall within the genetic variability of B. edulis.
The lack of resolution in the B. edulis clade due to low variability of ITS and GAPdH, suggests that there is an overestimation of the significance of morphological and ecological characters, as was already made apparent by the study of Van der Linde (2004). We therefore consider all taxa in the B. edulis clade as belonging to one morphologically variable species.
GAPdH data was able to improve the support of the recognised clades from the ITS data but not resolve relationships, especially within the B. edulis clade. In conclusion, host plant specificity has a very restricted value for the recognition of species in sect. Boletus. Boletus edulis appears to be associated with a large number of host trees, both deciduous and coniferous. Boletus pinophilus seems to be the only species within the section which has a rather strict association with Pinus, although it sometimes also is found in pure Picea or Abies stands. The latter is sometimes referred to as B. pinophilus var. fuscoruber. Boletus reticulatus and B. aereus are restricted to a number of Quercus species. We therefore recognise four species throughout Europe:
B. aereus, B. edulis, B. pinophilus and B. reticulatus."

(I have stressed that key phrase)

there's lots more . . . . . - essentially B. aereus, B. edulis and B. reticulatus form a group within that outlined above; B. pinophilus separates out from these and is clearly conifer-dependent (it was, for example, the only one out of the four that failed to form mycorrhizas artificially with Cistus species in another study)

cheers

Chris

I'll post further extracts from the literature when I can summon up the power to care

[SheffieldLass]

Originally Posted by SheffieldLass

Just looked back through my photos and this shows the stipe much more clearly. paler reticulation at the bottom, but does seem concolorous with the stipe higher up. I know that spot is mainly purple beech but there may well be the odd oak amongst them. It's only 10 minutes walk up the road so easy to check that ....

Been and checked and there is an oak in that spot, surrounded by beech. The occasional birch too. No pines though there either. And no other conifers. I'll do a check on the cap cells of the one I found yesterday see what they are like.

But I need to do a washing up job on the coverslips first . And buy some new ones ... they're all beginning to break, not many left of them left intact.