Observation 120350: Amanita sect. Vaginatae sensu Zhu L. Yang
When: 2012-12-15
No herbarium specimen

Notes: not sure if this got vouchered.
IDed by Adrian Lee and DLV.

Proposed Names

9% (2)
Recognized by sight: white form.

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Eye3 = Observer’s choice
Eyes3 = Current consensus

Comments

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thanks Rod.
By: Debbie Viess (amanitarita)
2012-12-19 04:25:39 CST (+0800)

I have seen it, and even have it in a paper form somewhere!

One of the white grisettes described is undoubtedly just a white phase velosa (which Wright admits is prob. true in the key).

The white one that “grays” also grays on the cap, which this specimen does not show, and on the UV, but no mention of the inner surface of the volva graying only.

Not a lot of deep description in the key to go much further.

No spore data from this grisette to send us one way or the other, either.

We do seem to see white forms of just about every common, colored amanita species out this way, eventually. This one most resembled a constricta, IMO.

This ID is merely a best guess-timate, with no hope of going further. I sincerely doubt that it was saved.

A draft key including some western North American white taxa in sect. Vaginatae.
By: R. E. Tulloss (ret)
2012-12-19 03:31:14 CST (+0800)

http://www.amanitaceae.org/content/uploaded/pdf/pnwcakey.pdf

It is a draft key to over 70 taxa of Amanita occurring between British Columbia and Baja California in Pacific coastal states and provinces of North America.

It is several years since it was last updated, but it does list several white species of section Vaginatae (mostly poorly known, granted) including at least one that has a graying volva.

The information comes from many sources including unpublished Mss. of A. H. Smith and Greg Wright.

I hope it is of some use to you.

It’s been on the web in one form or another for along time, probably people have forgotten that it exists.

R

I am well aware of your vast amanita experience w/species worldwide…
By: Debbie Viess (amanitarita)
2012-12-19 02:15:48 CST (+0800)

but we are talking exclusively about western species here, and what this one could be, compared to what we have collected and documented in the west.

have you observed pure white forms of some of the other grisettes from Europe that normally have gray inner volvas, and were their inner volvas also gray even in a pure white form? If the graying of the inner volva, even in white forms, is the same process within that related group of grisette species, then it would be reasonable to apply that feature to our white grisette here, and thereby eliminate constricta as a possibility.

otherwise…I am not entirely convinced.

I have also seen constricted volvas in other western species…
By: Debbie Viess (amanitarita)
2012-12-19 01:11:01 CST (+0800)

pachycholea, velosas, etc., but other features can help to distinguish species, even if they have a constricted volva in common. the flaring of the upper volva is one feature. if a microscope is the only way to nail IDs though, none of the IDs at the NAMA foray were valid.

how many white constrictas have you observed? and did they have a graying inner volva? Yes, I also commonly observe that feature in colored forms. I hear you that it is some sort of necrotic process, but if pigmented, and the fruit body is entirely lacking in pigment, how could that occur?

maybe there is a strictly pure white entity out here in the west that is unnamed, god knows we anticipate plenty of cryptic grisette species with further DNA elucidation, but other than the cap color, it sure looked like other constricta material to me. is this ID somewhat ambiguous? sure. but i still think that it was a constricta from what i saw.

and I’d lay odds that no one bothered to save it.

your messages came directly to me in my inbox and I just replied directly.

another response to another note
By: R. E. Tulloss (ret)
2012-12-18 23:59:52 CST (+0800)

It would be useful to keep this whole interaction on-line I think.

Apparently, I didn’t make my point clear.

DV:"yet this amanita had no pigment whatsoever, so why expect the inner volva to be colored? we see both gray capped and brown capped constrictas, pretty easily separated from protecta. here’s one example from the BA….inner volva gray, pinched and flaring:

http://mushroomobserver.org/93292?q=vWgd”;

Because I have over 20 years experience with the anatomy of species in sect. Vaginatae that have graying volvas that are white at first. I gave a brief list in my previous posting.

DV: “the sac on the white grisette was thin, pinched and flaring, the cap with small warts, all of which are typical of constricta.” [Comments about the NAMA foray removed]

That form of sac is very common in sect. Vaginatae. The process of expansion of the STEM stretches the volva upward constricting it. The expansion of the CAP causes a flaring somewhere in the volva above the constricted region. The choice of the name A. constricta should not be taken to imply in any way that this is the only species with a constricted volva. See, A. supravolvata, A. amerifulva, A. mobilimanica, etc.

DV: “The velosas have an apricot staining on their inner volva… and to all appearances that IS related to color transference of the cap color. I sometimes see the same thing in phalloides, with the inner volva colored yellow.”

I have no doubt that you are correct about velosa and the same applies to many, many taxa that have relatively robust volvas and pigmented pilei. In writing about the A. crocea group, I pointed out that gelatinization that would ordinarily (in many species) separate the cap surface from the inner surface of the volva takes place INSIDE the cap skin in some species causing a thin layer of the cap’s skin to be placed like wallpaper on the inner surface of the volva. This can carry the pigment of the pileus skin with it. It is also possible that, without this additional mechanical redistribution of pigmented hyphae, pigment could be created on the inner surface of a volva because the primoridum is is a node of wet chemistry and pigment development may not be restricted completely to the pileipellis. The point is that pigment on the inner surface of the volva derives from an entirely different process than does the necropigment in the dying or dead inflated cells within the volva. The latter is the common process of coloring or recoloring the volva in all the amanitas in (for example) the ceciliae and __submembranacea_ groups.

In other words, I do not see any reason to use the name “constricta” for this entity. It is some white entity belonging in section Vaginatae.

DV: “At any rate, all we had was macro ID. Grisettes are always a challenge, white forms more so.”

My point is that you don’t have any ID. Species of section Vaginatae are a challenge, but they’ve been studied rather carefully in some parts of the world for several decades. In some parts of the world, several white species of the section are rather well understood.

R.

In response to your note.
By: R. E. Tulloss (ret)
2012-12-18 21:23:14 CST (+0800)

The graying of the cells in the volva of Amanita constricta is not due to pigment leakage from the pileipellis as you suggest, but due to the progressive build up of necropigment from decaying/discoloring inflated cells in the volva.

Also, the idea that the cap of constricta is gray (at least the idea put forward in the protolog) is due to the fact that Thiers and Ammirati mixed multiple species in their description…including the distinctly gray-capped A. protecta. This is reported, if I remember correctly, in my paper concerning type studies in the Vaginatae published in the early 90s. From the evidence that I have accumulated, the cap of A. constricta appears to be brown.

A graying, weakening volva (seen in diverse species from North America and Europe and worldwide in the subacrctic) seems always related to pigment (probably necropigment) developing in the inflated cells of the volva—see, A. submembranacea, A. mortenii, A. castaneogrisea, A. sinicoflava, etc.

R

If this is a white form of A. constricta,…
By: R. E. Tulloss (ret)
2012-12-18 12:41:00 CST (+0800)

would it not seem reasonable that it would have the typical graying volva?

There are quite a few reported white taxa or possible taxa in sect. Vaginatae in the west with white volvas. Did anyone check spores?

Rod

Created: 2012-12-18 12:22:17 CST (+0800)
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