Observation 67720: Amanita malleata (Bon) Contu
When: 2011-05-20
Who: zaca
No herbarium specimen

Notes: Found in a mixed forest, mainly with _Quercus but also Pinus, Fagus and others.
I think that the camera reproduced quite well the colors. In the cap of the button we can find dominating brown tones but also some greenish tones. Nearby there was a mature specimen, already fallen. This specimen preserved this greenish tones at maturity, mainly at the margin and adjacent zone, having the center darker than the corona. Its stem as something like a zig-zag on it.

Proposed Names

ret
54% (1)
Eyes3
Recognized by sight: from zaca’s descriptions both macro- and microscopic and the images…plus old research into A. malleata.

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

Eye3 = Observer’s choice
Eyes3 = Current consensus

Comments

Add Comment
Quoting ret:
By: zaca
2011-05-25 14:41:36 CDT (-0500)

“suddenly seemed like something to mention”, I’d say this is the advantage of knowledge.
Best regards,
zaca

You’re welcome
By: R. E. Tulloss (ret)
2011-05-25 14:01:16 CDT (-0500)

I had no idea what to say until you posted the spore data. When I saw the average Q around 1.2, malleata suddenly seemed like something to mention.

So you have to blame yourself for looking through the microscope. :-)

Very best,

Rod

Acknowledgment.
By: zaca
2011-05-25 12:54:27 CDT (-0500)

I feel very grateful and indebted to Dr. Tulloss for his help in the classification of the specimens belonging to genus Amanita that I have placed here. This specimen is now the second in a short period of time, and I alone would have much difficulty in reaching the correct classification, if I ever could do.
Thanks also to the tnihekr and to Yooper Shroomin for their kind words about this observation.

Great Observation
By: Charles Seltenright Sr (Shroomin Yooper)
2011-05-25 08:34:58 CDT (-0500)
I’d like to suggest that this is close to Amanita malleata
By: R. E. Tulloss (ret)
2011-05-24 22:09:49 CDT (-0500)

The spore data suggests the possibility that the species represented here is Amanita malleata.

There are many names that have been generated for taxa with average spores broadly ellipsoid to ellipsoid (with overall average Q < 1.30 for all spores measured in a “good-sized” sample), a cap including a grayish tint, a volval sac that is somewhat weaker than that of other species in section Vaginatae (but doesn’t turn gray as in A. submembranacea). And I’m rather certain that there are fewer species than there are names.

Without zaca’s microscopic data, no progress could have been made by an American who knows the group from dried material (e.g., type studies).

With zaca’s data, one can at least point to a sample taxon that would fit the data fairly well. I generated a comparison sporograph on

http://www.amanitaceae.org/?User_sporograph

There was a fairly good match between zaca’s data and the data made up from type studies of malleata and two of its synonyms that have valid names.

If interested in further details, one can see

http://www.amanitaceae.org/?Amanita_malleata

Very best,

Rod

nice pic man!
By: jimmiev
2011-05-24 18:10:20 CDT (-0500)

love the first pic

Data from microscopy added.
By: zaca
2011-05-24 17:55:37 CDT (-0500)

I already uploaded some photos from the microscopy. For the spore I obtained the following measures:
(9.7) 10 – 12.3 (13.9) x (8.2) 8.9 – 10.1 (10.6) µm
Q = 1 – 1.3 (1.4) ; N = 50
Me = 11.2 × 9.5 µm ; Qe = 1.2

Created: 2011-05-20 16:29:03 CDT (-0500)
Last modified: 2011-05-24 22:12:53 CDT (-0500)
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