Observation 110426: Amanita bisporigera G.F. Atk.

Yellow with KOH on cap.

Proposed Names

57% (1)
Eye3 Eyes3
Recognized by sight

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
Thank You Stephen.
By: groundhog
2013-06-27 10:48:42 CDT (-0400)

This material has been accessioned into Rod’s herbarium.

two types of “lack of toxins”
By: Sam.Schaperow (SamSchaperow)
2012-09-20 08:52:09 CDT (-0400)

1. One type is that there are zero toxins present, such as to have zero amanitins: Based on the available data on “multiple copies of the amanitin gene”, I see what you mean. Yes, so very unlikely that there are no toxins, per this paragraph’s definition of a lack of toxins being zero toxins present.

2. Or, if we define a lack of toxins to mean insufficient amanitin to cause a toxic effect (just as some mushrooms contain trace amounts of toxins, but not enough to be toxic, thus from a toxicity perspective can be called free of toxins, though containing small to trace amounts of amanitin): By this definition, and I see you’re saying some specimens of what we call A. bisporigera contained “very low concentrations of amanitins”, then yes the question would be is this an intra-species or inter-species phenomenon.

For slugs, it would be nice to know how they respond to high-concentration amanitin Phalloideae.

The difficulty is that there are multiple copies of the amanitin gene in species like…
By: R. E. Tulloss (ret)
2012-09-20 07:12:00 CDT (-0400)

bisporigera. It is very unlikely that all of them would be altered sufficiently to eliminate then all. They have sustained alteration over the millenia (at least tens of millenia, I think), but (so far) these alterations have just created other amanitins with slightly different chemistry. I never want to discourage anyone from collecting data. Science is about hypotheses, not about absolutes. Right now, given what I’ve learned from recent researchers working on amanitins (check out the papers of Heather Hallen who wrote the paper demonstrating that there were genes that programmed amanitins directly).

There are individual specimens of A. bisporigera that have very low concentrations of amanitins and others that have very high concentrations of amanitins. Nobody knows why. There might be an angle there. On the other hand, it might be easier to see if slugs store the toxin in their bodies or have some other way of isolating themselves from the toxin. On the other hand, that might be capable of digesting it. One of the terrors for humans is that we cannot digest it.

Very best,


By: Sam.Schaperow (SamSchaperow)
2012-09-19 23:19:06 CDT (-0400)

If you’re saying that white Phalloideae all came after amatoxin-containing Amanitas, then I’d see why it is so unlikely there could be amatoxin-free white Phalloideae. On the other hand, is it very unlikely that the evolutionary tree would go like this (some simplification may be present ahead):
Amanitas to
Phalloideae w/amatoxins to
White Phalloideae w/amtoxins to
White Phalloideae w/o amatoxins (essentially another evolutionary step w/enough differences to be a different species and where they lose the amatoxins)

I’d guess, then, that the best way to see if there may possibly be amatoxin-free white Phalloideae would be to use the Meixner test on many white Phalloideae. In the unlikely event one were to ever be found w/o amatoxins, I’d think it should be a good candidate for sequencing.

Sam Schaperow
P.S. I think this is the link Rod set up that somehow didn’t work due to link issues. I hope this one works and is the correct link (if so, I think the new info. is found on the 9/19 RET comment on the unpublished molecular data): http://mushroomobserver.org/110133?q=e4IW
But, http://mushroomobserver.org/79375?q=eCYk seems to contain even more info. on this molecular subject. And, all of the [currently] four observations contain something about the molecular info. They can all be found here:

So far, Sam, …
By: R. E. Tulloss (ret)
2012-09-19 22:23:27 CDT (-0400)

all the species in sect. Phalloideae that have pigment distributed suggesting radial fine lines (as in phalloides) and all white taxa are in the group that evolved after the evolution of the gene for producing amanitins. All the nonpoisonous taxa in the Phalloideae have a cap with a solid dark color. The only ones in the latter group that are presently known are in southeast Asia. We could have species like that in the U.S., but we haven’t found any yet…or if we’ve found them we haven’t confirmed absence of amatoxins.

A lot of work on this group is being done in China using both morphological and molecular techniques. Their results have been impressive.

Very best,


Batesian mimicry
By: Sam.Schaperow (SamSchaperow)
2012-09-19 22:01:11 CDT (-0400)

I wonder what the chances are that all of the following conditions hold true:
-Slugs eat A. “bisporigera”.
-Said slugs are not ill or dead from doing so.
-These slugs survive well not due to being unaffected by the toxins, but that there are entirely different species of Amanitas that look just like what we’ve called A. bisporigera, yet lack deadly toxins [not due to variation amongst the same species, but due to being different species that lack the toxins].

If some slug species can differentiate between those with and w/o the toxins (such as to sense the toxins themselves, just as we can sense the nauseating Russula toxin via tasting the acridity), that would be quite interesting.

However, whether the slug part of the above holds any reasonable possibility of truth or not, the part about different species that look the same but aren’t, and lack the toxins, may be amongst the fungal world’s greatest Batesian mimics.

I think that would be worthwhile.
By: R. E. Tulloss (ret)
2012-09-19 21:34:23 CDT (-0400)

I found something that was otherwise like bisporigera this year that didn’t turn yellow with KOH. There are mysteries out there….


By: Stephen Russell (Mycota)
2012-09-19 21:20:09 CDT (-0400)

I will start saving more of these as well. The only reason I saved this one is because I did not have KOH on me.

By: R. E. Tulloss (ret)
2012-09-19 21:15:29 CDT (-0400)

We had an interesting development today (check out the pages now named
Amanita “sp-O01” on MO). It looks like it will be worth while for awhile to hang on to material that we would call A. bisporigera (I see that you are doing just that with this collection). I have had several indications in recent months that there may be more than one destroying angel reacting positively to KOH and having subglobose spores. The same thing is happening in other parts of the world. Dr. Yang wrote to me that he thinks that the number of taxa in the white, destroying angel group in eastern Asia probably is twice what he thought in 2005.

Very best,


Created: 2012-09-19 19:13:01 CDT (-0400)
Last modified: 2018-01-02 23:15:25 CST (-0500)
Viewed: 206 times, last viewed: 2018-04-10 18:10:17 CDT (-0400)
Show Log