Odor not distinct
Mixed deciduous tree.

Species Lists



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

= Observer’s choice
= Current consensus


Add Comment
DNA delivers the verdict — it’s R. rhodosanguineus alright
By: I. G. Safonov (IGSafonov)
2019-01-05 18:02:22 EST (-0500)

A clean, contiguous and super-long TEF-1 of 1441 bps has been obtained from this collection by Dr. Kudzma and uploaded to this post. The sequenced region is between the TEF1F and EF1-2218R primers; the two primers have been edited out. The typically sequenced region between and including the EF1-983F and EF1-1567R primers is 611 bps long and is roughly in the middle of this read. There are only 3 ambiguities present in the whole sequence: R (A/G) and two Y (C/T); this means there are 2 3 = 8 possible haplotypes.
A BLASTn search of the whole sequence gave two high-scoring hits with Ernst Both’s accessions of Rubroboletus rhodosanguineus:
MG897426 = “R. rhodosanguineus voucher BOTH4263” = 1143/1143 = 100% match
KF030412 = “R. rhodosanguineus voucher 4252” = 1160/1166 = 99.5% match (1 mismatch, 1 ambiguity in 284926 and the other 4 are likely editing errors in KF030412 because they are embedded in the 18 opening characters of the read in the EF1-983F primer)
Also, alignment of this sequence with the TEF-1 of Eva’s obs 284926 shows that they differ only in 5 ambiguous positions shared in the common overlap of 1257 bps. Of course, a number of matching haplotypic combinations are present in both organisms.
While the identity of this collection is no longer in question, uncertainty still remains regarding the identity and taxonomy of B. rubroflammeus A.H. Sm. & Thiers. Conspecificity between the two taxa cannot be completely ruled out in the absence of genetic data for comparison. Other than Smith & Thiers holotype, M. Kuo’s voucher is the only material that best resembles rubroflammeus :

B. floridanus
By: Jason Bolin (
2018-06-23 07:39:56 EDT (-0400)

Igor, I have changed my vote to “could be” for both proposed names for this observation. I think you would agree that is fair.

Singer’s original description of B. floridanus as a subspecies of frostii has no bearing on this debate. There were many mushroom described from a single collection between 1890 and 1950 and many of them were poorly described. Floridanus is a true chameleon and seems to change by the hour. I would not call that an important clue in this situation.

The color of the stipe of B. floridanus is extremely variable. I have even seen it had a PURE YELLOW stipe with no red at all. This was due to water content and age. I will share this observation later today so you can see. The colors of the stipe of the observation we are discussing are perfectly in line with B. floridanus.

I agree with you regarding the geographic problem with this observation vs. where B. floridanus is reportedly found. That doesn’t mean B. floridanus isn’t found in Kentucky. I believe Jay Justice has fond B. ananans from Missouri and that species is described as coming from the same areas as B. floridanus. The range of most boletes has not been determined, especially those occurring in the Southeast.

Lastly, you mentioned the cap context of this observation… While I agree that the context texture seems to be a bit off from B. floridanus, I would further comment that Rubroboletus rhodosanguineus’s cap context is described as being yellow. This observation shows white flesh. That could be because it stained blue and resolved to blue but we would need Dario to tell us how long he waited to take the pictures after cutting it. The white context would also be an aurgument against B. floridanus btw.

I will review Logan’s Rubroboletus observations today if I have time.

Follow the literature, Jason!
By: I. G. Safonov (IGSafonov)
2018-06-23 00:54:20 EDT (-0400)

Start with Herr Professor Doktor Singer’s The Boletinae of Florida. Singer originally described floridanus as a subspecies of frostii. That’s an important clue. Then you have Ortiz-Santana et al. Boletes from Belize and the Dominican Republic. The authors write in their summary: “Boletus floridanus is characterized by the grayish red to intense red colors on the pileus and stipe…”. The “authentic collections” of B. floridanus from the link I supplied in the previous comment are reliably identified collections by Prof. Baroni. They look nothing like Dario’s bolete. Next, BENAs’ pix of floridanus are very similar to those seen on what’s been identified as floridanus on MO, but different from the boletes in this observation. A solid gestalt picture begins to emerge… How is that for “a valid reason”?
To begin with, Dario’s collection is characterized by the uniform purplish-pink color of the pileus, not the “grayish red and intense red” described above and seen in the relevant pix of floridanus. The context of floridanus is frequently marbled, but 285485 has a homogeneous “marshmallowy” texture. IMO, the overall appearance is more in line with it being a Rubroboletus taxon (e.g., rhodosanguineus: obs 250470). And then we have the geographic factor for floridanus I referred to below… Maybe Dario’s collection is not rhodosanguineus, but IMO it’s more likely to be a Rubroboletus than B. floridanus.
I was also frustrated by your “I would call that floridanus” vote based on zero evidence you presented to defend your proposal other than your vague references to what you’ve been collecting in FL and posting to MO. By the way, I gave you proposal a generous “doubtful” vote, not “not likely”. Then you haven’t answered by question about Logan’s presumed Rubroboboletus collections, some of which have more of a chance being floridanus on paper, at least based on the geography. However, many of them look more like Dario’s bolete instead, which gives initial credence to the fact that the distribution of Rubroboletus-like taxa span the entire width of the USA… Instead, for some reason, you chose to dwell on this obsie.

By: Jason Bolin (
2018-06-23 00:08:51 EDT (-0400)

Logan, take a look at my observations. I’m really bad at this web site still and can’t figure out how to copy and paste observation numbers LOL. I have a few “collection shots” of floridanus that show every color, shape etc.

I get it, Jason
By: Logan Wiedenfeld (LoganW)
2018-06-23 00:01:03 EDT (-0400)

I look at something like obs 320467 and am inclined to call it floridanus since I know the pore surface is so variable. (It was also a stone’s throw away from a bunch of more obvious floridanus.)

Still though, the deep red pore surface in mature material (the pore surfaces of my floridanus are usually rusty orange at this point), the smooth uniformly colored cap – these seem different.

Edit: I don’t know what I was talking about re the pore surface. In my head, I was seeing red. These are clearly not quite red.

By: Jason Bolin (
2018-06-22 23:47:48 EDT (-0400)

Thanks for the reply Logan…

Every time I think I “know” all of floridanus’s shapes, sizes, colors, staining… it jumps up and proves me wrong. I have even found specimens that do not stain at all on cap or stipe and barely on pores. I don’t take stipe shape or stature into account much since they grow quickly and may stretch out if they need to escape a substrate.

I’ll reiterate that I’m not saying this observation isn’t rhodosanguineus but it’s irritating me more than a little that Igor is voting “not likely” to my suggestion of floridanus without a valid reason.

I see
By: Logan Wiedenfeld (LoganW)
2018-06-22 23:36:41 EDT (-0400)

floridanus fairly often too, and what seems off about this collection vis a vis floridanus is a) the stature, particularly the length of the stipe relative to the diameter of the cap, and b) the consistent red of the cap color. The ones I’m used to seeing tend to be more squat, with clubby bulbous stipes, and tend to have different shades of red on the cap. They also tend to have more orange, both on the stipe and poresurface.

But I agree that they are sometimes wildly variable. I’ve mistaken them for other red-pored reticulate boletes. The amber droplets on surface are the best indicators, in my opinion.

By: Jason Bolin (
2018-06-22 23:26:26 EDT (-0400)

Igor I’m asking a valid question and you voting “doubtful” for a proposed species doesn’t make sense. If there is a reason you think this is rhodosanguienes let’s hear it. I’m not contending I am right and you are wrong, I just want to know the reasoning behind the ID.

By: Jason Bolin (
2018-06-22 23:17:27 EDT (-0400)

Also, I’m not sure what you are referring to regarding an authentic collection of floridanus from Belize. Singer described floridanus from Florida in 1945, or 1946. I believe any authentic specimen would be from the type collection area.

Floridanus isn’t very close to frostii at all except for the liquid exuded from the pores.

I guess my question is still unanswered regarding the species originally chosen for this observation. I’m trying to understand why rhodosanguineus was chosen.

By: Jason Bolin (
2018-06-22 23:07:32 EDT (-0400)

Igor I have posted several observations of B. floridanus that you can view. It is a true chameleon. Pores that are yellow, orange or red… stipe that has red reticulation over a red and yellow ground color and all parts stain blue, unless they don’t which sometimes happens due to water content or environmental conditions.

For me, unless I’m missing something about this observation in particular, this is B. floridanus.

Why floridanus?
By: I. G. Safonov (IGSafonov)
2018-06-22 16:30:45 EDT (-0400)

It’s my understanding that floridanus looks more similar to frostii than anything else. BENA doesn’t compare floridanus with anything other than frostii. Biogeographically, floridanus is a denizen of the Atlantic Coastal Plains, where it occurs from TX north to NC; BENA says floridanus is also known from TN, but it could just be a case of mistaken identity for the spores of floridanus and rhodosanguineus are similarly-sized.
I am sure you have seen Logan W’s multiple posts from Baton Rouge, LA, of what presumably is a Rubroboletus species or two. What do you think about those collections given that they come from the area when floridanus is expected to be found?
I will be submitting 285485 for sequencing this fall, so we’ll hopefully find out about its generic affiliations toward the end of the year.
Finally, were are the pictures of an authentic collection of floridanus from Belize:

By: Jason Bolin (
2018-06-22 10:04:00 EDT (-0400)

Everything I see in the photos of this collection leads to Butyriboletus floridanus. What am I missing that would make it Rubroboletus rhodosanguineus?

Thanks, Scott
By: dario.z (dario13)
2017-08-07 22:50:19 EDT (-0400)

Collected for Igor.

The weirdest thing to me are the yellow pores
By: Scott Pavelle (Scott Pavelle)
2017-08-07 22:34:32 EDT (-0400)

According to BENA, Rubroboletus rhodosanguineus can have yellow pores as an infant but they quickly become bright red before aging to an orange- or coral red in old age. These look distinctly yellow.

I would have made the same guess, but I don’t have a lot of confidence in it. I wonder if it isn’t something new? I hope you’ve kept an herbarium sample.

What a beautiful find Dario! Lovely.
By: Scott Pavelle (Scott Pavelle)
2017-08-07 22:23:20 EDT (-0400)

Here are my notes on rhodosanguineus:

  • Yellow cap flesh tastes sweet, smells of over-ripe fruit when fresh & perfume when dry, & blues quickly before resolving to dull grayish-blue.
  • Viscid red cap gets brown tones & fissures in age, & stains dark red-purple before fading to gray.
  • Red pores (below yellow to brownish-olive tubes) stain quickly blue.
  • Yellow to pale pink stem has red netting, becomes purple-red at the base, often has brownish spots, & stains blue (becoming green in the reddish areas).
  • Yellow stem flesh, w/burgundy-red & golden zones by the base, quickly blues.
  • May grow in merged clusters. Likes oak, particularly red oak.

I would check on the odor again when it’s dried. That would be confirmation. It’s usually a more northern mushroom also, isn’t it?

Again – a truly beautiful find, with great photos. I’m envious.