Observation 140549: Amanita aestivalis Singer ex Singer
When: 2013-07-10
0 Sequences

This white Amanita sp. was collected in mixed woods (mostly Oak and White Pine). The spores show a stronger amyloid reaction of ruptured spores in Melzers, which I also see in other species that I believe are in the subgenus Lepidella, section Validae. The white spore print was taken on glass and these mature spores were used for microscopy. The above mentioned amyloid reaction and shriveling of spore contents is seen in Melzers, while 20% glycerin/water was used when measuring spores. The 20 spore average was 9.2 × 8.7 microns with Qm = 1.06 (globose to subglobose).


The spores show a stronger amyloid reaction of ruptured spores in Melzers.
The 20 spore average was 9.2 × 8.7 microns with Qm = 1.06

Proposed Names

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

Eye3 = Observer’s choice
Eyes3 = Current consensus


Add Comment
You’re welcome.
By: R. E. Tulloss (ret)
2013-07-23 13:25:00 CDT (-0500)

I have a lot of data on phenoloxidase spot testing that has never been published. It is distributed over many separate taxon pages on WAO.

Very best,


Thanks for the Spot Test info …
By: Linas Kudzma (baravykas)
2013-07-23 11:52:41 CDT (-0500)

and references!


For references on spot testing for phenoloxidases, see
By: R. E. Tulloss (ret)
2013-07-22 15:20:24 CDT (-0500)

papers with C. D. Marr as co-author in the WAO bibliography:


The paper with Massart is this one:

Tulloss, R. E. and F. Massart. 1998. Quelques observations courtes et preliminaires sur Amanita asteropus et Amanita aestivalis. Doc. Mycol. 27(109-110): 73-76, 119, pl. 5(figs. A-D). [In French.]

The translation to French was by Dr. R. Courtecuisse, the editor of Documents mycologiques.

I should scan that article and put it on-line.

Very best,


Spot tests for phenol oxidases in fungi….
By: R. E. Tulloss (ret)
2013-07-22 15:15:23 CDT (-0500)

The paracresol test is a neat thing that I picked up back in the late 1970s or early 1980s (or both). Unlike other phenolic compounds it reacts only with tyrosinase. Common tests react with multiple enzymes. Another specific spot test is with syringaldazine that turns purple only with laccase.

I was quite used to seeing very little reaction for syringaldazine until the day at NEMF foray in upstate New York (I think the town was called Mexico… was near to such a town), I split a large specimen of Amanita abrupta and “painted” the surface of the section with syringaldazine. My mind was blown. I got an intense purple reaction across the entire surface from the warts on the cap to the tip of the bulb. That reaction is very, very rare. I wish I had a photograph; but I don’t.

There is one photograph of the reaction on WAO…on this page:


Very best,


Fascinating ….
By: Linas Kudzma (baravykas)
2013-07-22 14:37:37 CDT (-0500)

I had no idea about the French intrigue backstory and that line “on the boots of GIs” is too funny!

I’m encouraged that you support my initial thoughts, which were after all based on what I found on amanitaceae.org. I’m glad I collected it. Oh and to be honest, I’d never heard of the 1% paracresol macrochemical test you mention in the Amanita asteropus write-up.

Thanks Rod.


Hello, Linas
By: R. E. Tulloss (ret)
2013-07-22 13:13:19 CDT (-0500)

Thanks for pointing me to this observation, Linas.

At present (at least) I would call these Amanita aestivalis because they fit the original description of Singer very well.

Morphologically they are very close to A. brunnescens and, genetically, the same is true; however, the genetic picture we have so far says that A. asteropus (of southern Europe) is equally close to A. brunnescens. I think that we may not have sufficient data (insufficient genes sequenced) because both pigment differences and (possibly pigment-production-related) other macrochemical differences (responses to spot test reactions) differ among the three mushrooms.

Given the available information, I am hesitant to view brunnescens and aestivalis as a single species. I would like more data first. It is easy to segregate collections into two groups by eye. Pure white, except for the disc, and very slow to stain/bruise on the one hand and pale citrine to shades of brown or grayish brown and somewhat faster to stain/bruise on the other hand.

This omits the butter yellow, European species, which is very distinctive.

I wrote a paper with Francis Massart some years ago when I was asked by him to defend the French mycological patrimony after a paper appeared saying that asteropus was only aestivalis brought to Europe “on the boots of GIs.” To the delight of Francis, we found several arguments to defend asteropus as European and not an American import.

Very best,


Created: 2013-07-21 22:06:51 CDT (-0500)
Last modified: 2013-07-22 19:18:26 CDT (-0500)
Viewed: 109 times, last viewed: 2017-10-12 14:58:11 CDT (-0500)
Show Log