Observation 146238: Amanita “sp-O01” Tulloss nom. prov.
When: 2013-09-23

Notes: I see Amanita bisporigera frequently and it is usually a fairly small, slender species matching published descriptions. This one I see in Wisconsin every year (several disparate sites), with mixed oak and conifers. It is very robust with caps becoming 8 inches across or more and a very stout stem. Saccate volva is robust but not especially deep. It is KOH positive, turning bright yellow on cap immediately. Others have offered other names including A elliptosperma (but that species is reportedly KOH negative).

Proposed Names

32% (2)
Recognized by sight
Based on chemical features: KOH positive; reaction was immediate

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Eye3 = Observer’s choice
Eyes3 = Current consensus


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Thanks Britt,
By: groundhog
2013-10-29 20:23:54 CET (+0100)

This material has been recieved and accessioned into Rod’s herbarium.

I don’t think we should ignore the sequences on GenBank…unless they are very fragmentary…
By: R. E. Tulloss (ret)
2013-09-24 20:35:58 CEST (+0200)

which happens. It is one thing to be skeptical of the names attached to the sequences and another thing to reject the sequences. If quality work was done, the sequence represents something out in the world. In the case of a sequence given the name of a species in section Phalloideae, the correctness of section can be checked with some confidence for sections represented by multiple nrITS and/or nrLSU sequences already in GenBank. This basic situation does exist for section Phalloideae.

Under this condition, it’s reasonable to grab a bunch of sequences from material collected in North America and compare them to new sequences from fresh, well-documented material. If there’s a sequence that doesn’t correspond to sequences from the newly collected material, then you better look for more material so that you can connect that sequence to a well-documented voucher.

Old sequences can be “proofs of suspected existence” for taxa that one hasn’t found oneself…even if we don’t have a name, we have a sequence. Now the sequence could be worth a little (fragmentary, unresolved nucleotides, etc.) or a lot (complete clean sequence of ITS, for example).

There’s a significant need for “do overs” because of incomplete sequences when it comes to nrITS in Amanita. Many sequences are fragmentary…a few are missing 2/3 of the characters. A signficant number are missing 100 or more characters from one or both ends of the proposed barcode gene.

Very best,


reminds me of A. ocreata…
By: Debbie Viess (amanitarita)
2013-09-24 18:47:11 CEST (+0200)

which also shows these very robust forms.

AS to DNA comparisons…rather than compare with amanitas of dubious identity on Genbank, why not just create a brand new tree with a broad spectrum of fresh, well documented specimens? Start fresh, as it were.

AS to KOH rxns, isn’t this variable, even within species?

Thank you, noble friend.
By: R. E. Tulloss (ret)
2013-09-24 02:21:44 CEST (+0200)

Very best,


oh, why not…
By: Britt Bunyard (Fungi magazine) (bbunyard)
2013-09-24 02:11:24 CEST (+0200)

I’ll add it to the list. On the way! -B

I forgot to say, Britt,…
By: R. E. Tulloss (ret)
2013-09-24 02:04:03 CEST (+0200)

that I’d like to see a spore-bearing specimen from this collection if you can spare it.

Very best,


The discussion with Britt and Jon took place on the page for…
By: R. E. Tulloss (ret)
2013-09-24 02:02:53 CEST (+0200)

observation 146235.

Very best,


Upon further discussion with RET
By: Britt Bunyard (Fungi magazine) (bbunyard)
2013-09-24 01:39:44 CEST (+0200)

could also be “Sturgeon’s Destroying Angel,” Amanita sp-O01. I have some additional notes to add on macrocharacteristics. In addition to KOH + reaction; odor is very pleasant almost sweet as in other A bisporigera types; taste is very pleasant too, as with other bisporigera types (indeed most other Amanitas excluding Lepidellas).

Created: 2013-09-23 21:02:23 CEST (+0200)
Last modified: 2013-09-24 02:01:40 CEST (+0200)
Viewed: 64 times, last viewed: 2016-10-23 20:50:36 CEST (+0200)
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