The volva on the yellow variant of A. amerimuscaria is usually nowhere near as yellow as on the intensely red variant. And, even the volva on the red variant becomes very pale (even white) quite quickly after exposure to sunlight. The only reliable ways that I know of separating amerimuscaria and muscaria are by microscopy (the thickness of gill tissues in cross-section and the size and (more subtly) shape of spores) and by the DNA sequencing work produced by Dr. Geml a couple of years back. If you would like the details of the microscopy, you can contact me through the email feature of MO. I hope to have graphical representations of the microscopic data on the new Amanita Studies website in a few months time. There is (and will be) a lot of content editing and software development still going on.

Very best,

Rod

and other pictures of this ob http://mushroomobserver.org/image/show_image/52834?obs=24035&search_seq=1201610&seq_key=954693 located in the same are are they the same species ?
is a truly washed out one

I would have a hard time calling this mushroom Amanita muscaria var. flavivolvata, because it does not have a yellow universal veil. “Amanita muscaria var. flavivolvata” is synonymous with, and deprecated in favor of, Amanita amerimuscaria.

I’m not sure if the veil color is a consistent enough character to distinguished the two species, but two species they are. If genetics is the only way to distinguish the two, then we are stuck.

I’m wanting to say this is not var flavivolvata, because the veil is not yellow.

These are not faded A. amerimuscaria.
Amanita muscaria var. formosa hasnt shown to form a coherent clade within A. muscaria, for now it may be better to call these simply a yellow form of A. muscaria.

I don’t believe that the DNA evidence supports the idea of the east coast yellow variety of A. amerimuscaria being interspersed with the western red variety of A. amerimuscaria.

The PNW yellows listed as var. formosa have been shown through dna to be the same as the European A. muscaria.

The picture there refers to var. formosa. I don’t think anyone can tell today what that is (no type collection is preserved), but it was described to have a yellow cap and yellow veil, found in a beech forest (=franchetii??).

click on Amanita muscaria one of the pictures in this observation is in the Description, should it be removed?

see http://mushroomobserver.org/24035?search_seq=1201610 and http://mushroomobserver.org/19821?search_seq=1201610 (this ones was the reddest but that being it was in the shade) and http://mushroomobserver.org/20286?search_seq=1201610

are all observations of this same Amanita (as far as i know) at least they were picked in the same area and I never found such startilng red forms as are found in Europe. even buttons were yellow…..i will dry some next time i find them…any one want a sample? in the fall….

I agree with Rod, this is not a yellow variant, it is a typical red one that has started to fade. Some that I saw yesterday were nearly peach coloured just from fruiting out in the open and being exposed to rain and sun, while others in the same area that were protected under the trees were the typical red colour.

The photographs look more like a fading A. amerimuscaria than the yellow variant of A. muscaria, but that’s about all we can say without dried material. I’m spreading my votes around on this one. Looks like we’re getting synonymous suggestions among the names. To my way of thinking A. muscaria in the strict sense is in the list of alternatives twice.

R.

A yellow form of A. amerimuscaria in the PNW? I’ve been under the impression that the pure yellow forms are A. muscaria in the PNW.

If the yellow and red form of A. amerimuscaria are interspersed in the west, how come we dont see that in the eastern U.S?

Since recent molecular studies show that yellow variants exist of both subsp. muscaria and subsp. flavivolvata and that an area of potential overlap of yellow populations of the two subspecies (someday separate species) occurs in the NW 48 US states and possibly BC, and since we don’t have a specimen to check, I think Irene has come up with a good solution. Since there is as yet no publication segregating two species, it is still correct just to give the currently used SINGLE species name no matter what infraspecific taxon (variety, subspecies, form, etc.) the mushroom might be if we could get it under a scope.

Very best,

R.

or possibly Amanita muscaria var. guessowii?

Amanita muscaria var. muscaria is no particular yellow variety, it just points out that it’s not any of the described varieties.