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Found in sandy soil in mixed woods close to creek, mostly hardwood, Hemlock nearby

3 robust specimens found together, the 4th (more slender, cap opened up) found about 1/4 mile away

Faint smell, possibly of ammonia (I have a hard time describing smells, but there definitely a noticeable, distinct smell)

Dimensions for the largest specimen

16 cm long

Cap 13 cm wide

The stem is hollow enlarges downward from 4 cm to 2 cm in width

When stem is sharply scraped (down to the “quick”), an immediate pink stain occurs, which rather quickly fades to a light brown

spore sizes:
(10) 10.5 – 14 x (5.5) 6 – 8 (9) μm


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I did a very quick check on the data that is in GenBank and that I was…
By: R. E. Tulloss (ret)
2015-10-22 07:01:48 CEST (+0200)

working with today. Without writing an essay, our nrLSU sequences combine to cover a region more than 1,420 characters long. In this region we see variation in 0.4% (6) of the character positions. The variation always involves only 2 possible characters…in the data that we have.

As we accumulate more data, it will be posted to GenBank and the links to the individual sequences will be in the upper portion of the techtab of the whetstoneae taxon page:

At the moment there are five (5) nrITS sequences and one (1) nrLSU sequence that have been posted in GenBank. We are presently processing six more nrITS and 3 more nrLSU and have several additional samples in the pipeline. The time to public availability on GenBank from the time of submission has recently been about 6 months for us.

Very best,


By: Steve Roberts (Mushroom World)
2015-10-22 03:33:56 CEST (+0200)

I’ll be anxious to learn how it all sorts out with other A. “whetstoneae” specimens.


We just got very nice nrITS and nrLSU sequences from this material.
By: R. E. Tulloss (ret)
2015-10-22 02:16:49 CEST (+0200)

Thanks very much for sharing your collection with us.

Very best,


I understand that the quotes are…
By: R. E. Tulloss (ret)
2012-07-12 05:18:39 CEST (+0200)

what the developers’ group would like to see on provisional names and code numbers. If I’m wrong about that, I’ll stand corrected. Well, I’ll be corrected standing or sitting. I’m trying to comply with a possible “standard approach” on provisional names. The quotes make it very clear that the name hasn’t been formally published.

Dr. Mary Whetstone was the person for whom Peck proposed the name (with masculine ending however) on a herbarium label at the New York State Museum mycological herbarium in Albany very near the end of his life. Dr. Whetstone was a pediatrician in the early 20th Cent. who helped found the Children’s Hospital of Minneapolis-St. Paul, worked for women’s right to vote, and was a founder (I think) and a (maybe the first) president of the Minnesota Mycological Society. Cool lady. She needs an amanita named for her.

Very best,


Like the sporograph…
By: Steve Roberts (Mushroom World)
2012-07-12 04:56:48 CEST (+0200)

that is way too cool! BTW, I also like the name “whetstoneae.” One thing that caught my attention is you assigned these specimens with the name “whetstoneae” in quotes. I see it listed more commonly on MO without the quotes. Is there a difference or is it the same name?

The color of the caps of all the specimens suggest A. whetstoneae.
By: R. E. Tulloss (ret)
2012-07-10 21:30:48 CEST (+0200)

I was just concerned about the shape of the volva and the short, robust stipe in the large specimen on the left.

I don’t know whether I have time to dig into the details on that one.

Very best,


You’re welcome.
By: R. E. Tulloss (ret)
2012-07-10 21:27:32 CEST (+0200)


It was interesting to see the material.

Amanita whetstoneae is not too hard to recognize in the field with the long-long-long, tubular volva, the size, and the fact that the cap and stem do not take on the brick red stains that become brown with age anywhere nearly as strongly as the other common exannulate species in sect. Amidella in the northern half of the U.S. (I really don’t know for sure what the range of whetstoneae is).

Amanita peckiana (which is also pale, even in age) can be easily distinguished from A. whetstoneae in several ways: partial veil exists briefly during the time before the cap expands, the volval sac is more cup-like, the spores have much higher length:width ratio (Q).

You can see the spore size-shape difference by going to the ?User+sporograph page on WAO ( ) and calling up the sporographs for both peckiana and whetstoneae; or you can see more taxa compared at once by going to the the directory page for section Amidella ( ) and clicking “see as sporograph” at the top of the green information box on the right of the page.

[The latter gives you more than your money’s worth. The “x” in brackets before a species name in the list of included sporographs is and “erase” function. Take out all the non-North American taxa from the comparison of sporographs (for strarters), and it will be easier to see the comparison of just the North American species. If you want to remove more information you can remove the sporographs based on data that don’t have a count of the number of spores used to obtain the spore range data. You can tell these cases because instead of having something like “[250/12/8]” in front of the range numbers, it will have “[ – / – / – ]” (without the blanks I inserted here for readability) instead.]

The sporograph function is very useful, and I hope that lots of folks who have the equipment and inclination to measure spores will learn to use the sporograph function to their advantage.

Very best,


Very interesting!
By: Steve Roberts (Mushroom World)
2012-07-10 17:11:02 CEST (+0200)

Rod, very interesting! Are you saying in picture 3c, that the large one on the left may not be A. whetstoneae, while you think the other 3 are? The tall open-capped specimen was the one found in a different location within .5 mile, but in similar habitat. The two smaller ones were found together with the large one on the left in picture 3c.

Thanks for taking the time to look at the material. We have found these several times, and its good to finally put a name to them.

The tall open-capped specimen is A. whetstoneae
By: R. E. Tulloss (ret)
2012-07-10 15:38:05 CEST (+0200)

I’m concerned that the large specimen to the left in bottom picture may be a different species. More later if there’s time.


Thanks, Steve.
By: R. E. Tulloss (ret)
2012-07-07 17:34:04 CEST (+0200)

The dried material arrived today.