Two buttons of bright yellow-orange cap with yellow remnants of universal veil on cap, step and base. Found in mixed woods.

Species Lists


Amanita muscaria var. guessowii Lithia Springs Granby 05220.jpg

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I did notice this, Herb.
By: Dave W (Dave W)
2017-06-29 11:01:40 NDT (-0230)

It actually reminds me of muscaria. I didn’t weigh in in on the muscaria proposal because I think muscaria buttons tend to be more completely covered by the UV. You and Jimmy (and C du Q) make a very good case for me to sacrifice some of my sacred Meltzer’s on an occasional “flavoconia”, especially when found in an area where I know that frostiana occurs. For example, obs 277759.

Given my (previous?) concept of frostiana, some of the photos at C du Q are really surprising. Mistakes do occur in field guides. But I would assume the folks at C du Q had subjected any ambiguous collection to Meltzer’s. I think another factor here may be the relative intensity of an amyloid reaction as per volume of the deposit, age of the fruit body, or some other factor. I brought home a “flavoconia” the other day that yielded a thin print and the amyloid reaction seemed to be quite weak, obs 280217.

I’ll ask Rod if he has an opinion on relative amyloidity.

In the “Remarks” section at C du Q…
By: Dave W (Dave W)
2017-06-29 03:41:09 NDT (-0230)

under the description of of A. frostiana, it says that the furrowed margin is what distinguishes frostiana from flavoconia. Since no furrows are seen on these buttons, there is no evidence regarding whether the spores are amyloid, and the basal volval structure of these buttons seems ambiguous, I don’t see how one can be confident this is frostiana. But I must admit, the color scheme of frostiana includes the possibility of more yellow that I had previously thought. Actually, a few of my own frostiana observations show yellow deposits atop the bulb.

At least one photo claimed to be frostiana at C du Q appears to not (obviously) exhibit any of the macro traits one cites as a reason to confidently ID frostiana sans microscopy/Meltzer’s. One of these photos looks like flavoconia.

Color scheme for flavoconia is also variable.

For another MO discussion about these two species, see obs 12136. Here we find evidence to support the possible lack of striations on button frostiana.

Agree that jimmiev shows same species
By: Mike Hopping (AvlMike)
2017-06-28 23:40:53 NDT (-0230)

The remaining question is, What is it? You and jimmiev could be correct, but that’s an impressive amount of yellow stipe on jimmiev’s observation and yellow in the collars of both observations. I don’t see much “stark white” on any of the three bulbs. Is the pink tinge in the vicinity of where the two buttons touch a trick of the light?

Yes, I saw Jimmie’s post…
By: Dave W (Dave W)
2017-06-28 23:24:54 NDT (-0230)

and also wondered about that one. Knowing whether or not the spores are amyloid would be very helpful in this, and Jimmie’s observation.

A. muscaria var guessowii allowed to be nonstriate as a button
By: Mike Hopping (AvlMike)
2017-06-28 22:57:03 NDT (-0230)

Between the pine association, rings at the base, tall and numerous warts, and RET’s statement on the page for A. muscaria var. guessowii: “The cap margin often becomes striate at maturity or in age”, I don’t think that species can be ruled out, despite the yellowness of the warts. Too bad information on the specimen is so incomplete.

The structure and shape…
By: I. G. Safonov (IGSafonov)
2017-06-28 22:24:59 NDT (-0230)

…of the UV on cap and stipe is the key to identification of this collection. Is it consistent with frostiana? Also, absence of marginal striation in young age wouldn’t necessarily eliminate sect. Amanita from consideration, as some taxa lack them altogether or the lines appear only in age.

Sometimes the striations on the cap margin…
By: Dave W (Dave W)
2017-06-28 22:24:07 NDT (-0230)

of a button of a species from section Amanita may be obscure. But this photo is very clear, and I see no evidence of tightly-packed striations. Also, the grainy yellow stuff on the stipe bases points away from frostiana, which ret describes as having basal bulb that is “starkly white”.

I thought…
By: Derek Ziomber (Space Time Matters)
2017-06-28 21:49:35 NDT (-0230)

that A. frostiana is supposed to have a radially lined margin. The color and stature looks like A. flavorubens to me, but that is a guess. If it bruised red on the stem, then I’d definitely go for A. flavorubens. There is too much yellow on the stem for A. muscaria.