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When: 2013-08-31

Collection location: Roberts Property, Cumberland Co., Tennessee, USA [Click for map]

Who: Steve Roberts (Mushroom World)

No specimen available

3 specimens, scattered along edge of mixed woods (mostly hardwood), including oak


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That’s right.
By: R. E. Tulloss (ret)
2013-09-03 14:48:30 MST (-0700)

My estimate used to be that I was correct about 75% of the time on field IDs in Amanita. I now think it’s harder than that. I’m hoping that genetic studies will help me improve in the most difficult areas (the species with the smallest fruiting bodies) by solidifying my species concepts. Maybe I can get back to 75% accuracy in the field. :)

Very best,


It appears we’re leaning more and more towards A. volvata…
By: Steve Roberts (Mushroom World)
2013-09-03 14:20:05 MST (-0700)

…it’s good to “get to know” this one. But, it appears it can be a tricky one with several very similar species.

The quick answer is " no."
By: R. E. Tulloss (ret)
2013-09-03 13:30:25 MST (-0700)

The old sequence for the Canadian material has no close match from material identified as belonging in sect. Amidella in GenBank.

Very best,


The breadth of the spores eliminates…
By: R. E. Tulloss (ret)
2013-09-03 13:20:41 MST (-0700)

sagittaria, dolichopus, and pseudovolvata. The short volva and strong pigmentation eliminate whetstoneae. The spore shape and strong pigmentation should eliminate peckiana. That’s pretty good coverage. I know that there was a genetically separated taxon from eastern Canada that was distinguished from volvata by the LSU gene in a 1998 paper. However, the Canadian material is not available to me at the moment (I’d have to re-borrow the material).

A lot of sequencing of amanitas has happened since the mid-1990s. I should go back and look at the sequence in question and see if it could be named based on genes sequenced in the last 17 years.

If I don’t give you a response on this soon, give me a push.

Very best,


Rod, Thanks for your suggestions with this ID…
By: Steve Roberts (Mushroom World)
2013-09-03 10:59:19 MST (-0700)

…since you say A. volvata would be a “reasonable estimate,” are there any other known species that could not be ruled out, based on the pictures and information given?

spore size
By: Steve Roberts (Mushroom World)
2013-09-01 22:34:48 MST (-0700)

9 – 12.5 × 6 -8 µm
and I would describe them as ellipsoid to broadly ellipsoid

Concerning spore measurements, if volvata is what you have, then…
By: R. E. Tulloss (ret)
2013-09-01 20:29:56 MST (-0700)

the spore measurements could be helpful.


I agree with your judgment on whetstoneae.
By: R. E. Tulloss (ret)
2013-09-01 20:28:28 MST (-0700)

Given the the fruiting bodies are rather large and volva is about the same in height and width, I think there’s also good reason to go for volvata as a reasonable estimate of an ID.

Very best,


more about these specimens…
By: Steve Roberts (Mushroom World)
2013-09-01 18:46:23 MST (-0700)

Sure, Rod, the specimens are still pretty fresh, though I haven’t done a full work-up. I also have a nice spore print if spore measurements would help.

Caps:6 to 9 cm across, 7 mm to 18 mm thick
Stipes about 10 cm long, including volva, 6 mm to 17 mm wide (not including volva)
Volva 3 to 4 cm wide, 3 to 3.5 cm wide
They have a bit of a mild, pleasant odor, but not strong
The warts on the cap are removable with a brush of the finger

You might remember we have found A. whetstoneae on our property close to creeks in sandy soil. These specimens were in grass in higher ground at the edge of a forest -I thought these were different than A. whetstoneae, mainly because the volvas weren’t as long and pronounced on these. Also, the caps seemed different on these and I don’t remember the A. whetsoneae having what I would term “brown floccose material” on the cap.

Hello, Steve.
By: R. E. Tulloss (ret)
2013-09-01 17:08:37 MST (-0700)

Can you give us an idea of the dimensions.

Very best,