|User’s votes are weighted by their contribution to the site (log10 contribution). In addition, the user who created the observation gets an extra vote.|
|I’d Call It That||3.0||5.23||1|
|Could Be||1.0||5.74||1||(Alan Rockefeller)|
sum(score * weight) /
(total weight + 1)
|User’s votes are weighted by their contribution to the site (log10 contribution). In addition, the user who created the observation gets an extra vote.|
|I’d Call It That||3.0||4.95||1|
sum(score * weight) /
(total weight + 1)
the more we will all learn. And the value of a sighting is increased exponentially. Less is less.
The choice of whether or not to read a detailed comment is wholly up to the viewer. Better to have that choice though, than just a photo to base your IDs on.
Keep on posting Rod, here, there and everywhere! AS someone once said of the BAMS list, it’s like sipping from an informational firehose…but in a GOOD way!
Sharing knowledge is not offensive. It is valuable information.
Your comments and discussions are always welcome. Pleas don’t stop. There is way to much more to learn. Thanks
Thank you Dr. Tulloss! Your summery of the the history of amanita taxonomy is great.
“Rest assured that I did collect it, and that it is safe and sound, and in very good hands.”
Good hands would be Rod’s hands, Haha!
He’s not going to beg for it though, well sometimes he begs for Amanitas.
tell me that there is no specimen.
I am delighted to hear that isn’t true.
Where do you come up with this stuff? Well I do agree that there has been enough discussion on this matter, but only because of the strange turn that it took. I would remind you that I never tried to suggest that the mushroom was anything in particular. As a lay person I enjoy collecting and eating mushrooms, and have since the late 1970’s which only goes to having some experience, but I make no claims to having any expertise on the subject especially to the criterion necessary for taxonomic classification, and the microsopic comparisons of these mushrooms. I simply made a couple of observations, and asked a question. And by the way, having read the reply to that question, I think I should be entitled to credit for taxonomy 101.
What I am qualified to comment on is the notion that this white Amanita is common in the east bay hills. Having spent a great deal of time in that area on a very regular basis, in the spring, and in search of A. velosa, it seems that were this mushroom common, I would have stumbled across it before now.
Rest assured that I did collect it, and that it is safe and sound, and in very good hands.
then no further discussion or at least firmer determination is possible.
nothing that you have put forth…white color, robust fruit body, scurfy stipe, length and depth of striations, thickish veil, inner limb to volva, hollow stipe, would rule out velosa. they are all variable characters, and all found in velosa, although sometimes uncommonly.
even the spores are a match, and that is the opinion of one who measures thousands of the damned things! (that would NOT be me.)
to prove your point, that this is something different, you need to come up with better, more compelling evidence. and to do that, you gotta save the mushroom.
Ret writes: “It’s truly a shame that errors that could be avoided are still being made in sufficient quantity to give the general reader of mycological books a false impression about what characters are (or appear to be) reliable for taxonomy and which are demonstrated to be unworkable.”
I thought the process of peer review was supposed to prevent this kind of mess?
And not really an easy one to answer. First of all, trying to identify characters that help taxonomically vs. characters that are very variable (plastic) and can mislead is one of the core activities of morphologically-based taxonomy. This has been going on for centuries and has become more formalized since the Renaissance. The publishing of books has made it much easier to pass on the knowledge obtained. And we know what the web is supposed to be able to do for us in terms of broadcasting information.
This could be an essay, but I won’t do that to either of us. Over time, things that could be measured with a precision tool (like an eyepiece micrometer) were sought out more and more because the data yielded through using such a tool could be repeated by another worker using the tool. Hence, spore measurements became important. (Of course there were people who just could not seem to do it very well and many people didn’t realize that measuring spores from different species could require different techniques, and it took a long time before the techniques were written down and made widely available.)
Without going through the whole story…
Even at the present time, when the determination of an Amanita takes looking through a microscope (rather casually, not measuring anything) at only two tissues (a gill cross-section and a thin, lengthwise slice of the flesh of the stem), people still don’t do that and just make a guess based on the most basic characters of macromorphology. Now those of us who are fairly confident that we can recognize an amanita from a car at 60 mph, probably get it right a lot of the time. But collector’s with more time on their hands and the mushroom in question IN those hands, if they fail to check the microscopy can (to put it simply) screw up. For example, Amanita cystidiosa (described within the last decade) is not an amanita with cystidia, it belongs to the group of lepiotaceous fungi, not the family Amanitaceae. So, first of all, We can know if something is a Limacella or an Amanita definitively from observation of the fruiting body. Amanita thiersii and A. calyptratoides look very different; but we can tell they are both amanitas despite all the morphological variety wrought by time and mutation.
In 1969, Dr. Bas published his thesis on the section Lepidella for the world. In order to do this he studied about 125 species in as much detail as the available material permitted and tried to render the data in terms of macroscopic and microscopic details. As was his job, he looked for the characters that he could count upon to give him a scheme into which he could place collections found later in as reliable a way as possible. Amanitas have many dozens of characters to choose from, more than many genera of agarics. He was aware that the reaction of spore walls to Melzer’s Reagent had surprisingly divided the genus about in half. This division corresponded fairly well to a system of ways for dividng groups of amanitas that had been improving over time. By 1940, E.-J. Gilbert had published a scheme that corresponds closely to our current scheme of seven sections placed in to subgenera within Amanita. Bas and Corner formalized this a bit further in 1962. Occasionally, one finds a novelty that seems to fall on a boundary between two sections; and this should be expected. Nevertheless, the division into sections works rather well at present.
In this 1969 thesis, Bas mostly found that species could be very well segregated by the microscopic details of the volva, the microscopic details of the subhymenium, the spore size range, the spore shape range, the structure of the cap’s skin (pileipellis), and the presence or absence or varying plenitude of clamp connections at the bases of basidia. With his set of methods for examining and measuring such characters, he was able to divide all known species of the section into small groups called “stirpes” (singular is “stirps”). He then was able to unify these groups into larger clusters that were segregatable by easily distinguishable groups of characters. These larger clusters Bas called subsections. Building a systematic view from the bottom up (stirps, then subsections) was combined with the on-going search for distinguishing characters that had little or predictable variation. He learned to be very cautious about the surface characters of the stem unless he could correlate them with an important, persistent piece of “clinically describable” anatomy. Scales on the stem of a species in sect. Vaginatae are strongly influenced by weather conditions, speed of growth (availability and relative plenitude of water), etc. However, flocculence on a stipe that is a deposit of gill edge cells that form a thick layer in a given species is a different matter. The flocculent material on the stems in some species of sect. Lepidella (e.g., A. thiersii) are part of the volva and comprise very distinctively shaped and sized cells. Amanita islandica has a floccose sheath on the upper several cm of the stem which is comprised of a thick layer of cells that allows the lamella edge to separate from the stipe during development and expansion of the fruiting body. This is a constant feature of that species. A similar sheath is to be found in A. arctica (another boreal to subarctic species like A. islandica).
We are returning now to the present case. One way to say this is that experience of several generations of mycologists leads a contemporary mycologist to describe all characters observed (like stipe surfaces splitting into recurved or downward pointing scales), but not to rely on some of the characters for use in defining core ideas about the species. The reason for this in the case of stem scales is that one sees the same thing over and over in species after species (e.g., in Europe A. virosa is often depicted as having a shaggy stipe, but is often found with a smooth one).
You are absolutely right to ask your question. It is another form of the question “What is [your/his/her] species concept of A. velosa?” It happens that generations of experience have put us in a position at this time in which we do not consider the very variable surface texture of the stipe to be a good element to include in a species concept in the genus Amanita. Nobody has done it, but if we were to find that flocculence on the stipe of A. velosa was derived from the gill’s edge cells and that it had a constant (range of) forms or positions on the stem, then that might turn out to be a taxonomically useful character. I can’t predict it.
Do we have the perfect set of characters? I doubt if there is such a thing.
For thirty years I’ve tried to refine the methodologies related to characters that are in use and to add useful new characters. As a result, I think that I have improved to some degree that ability to describe species concepts in sections Caesareae and Vaginatae, and (to a lesser degree) Amanita and Amidella.
That’s the way it has worked over the years. There are lots of people writing books and articles who don’t pay attention to the gathering of knowledge about taxonomic methods. These people write papers that use odd characters dependent on weather conditions or infection by parasites to define taxa in Amanita. It’s truly a shame that errors that could be avoided are still being made in sufficient quantity to give the general reader of mycological books a false impression about what characters are (or appear to be) reliable for taxonomy and which are demonstrated to be unworkable. In 2004, varieties of A. muscaria were still being described or supported in use based on dark hyphae of a hyphomycete coloring the universal veil (highly unlikely to be a genetically controlled character) or the accidental disposition pattern of universal veil on the lower stipe and the top of the bulb.
I hope all this helps somewhat in understanding why some characters seem to be “ignored” from a taxonomic point of view.
I don’t claim that this little riff is anything more than a spur of the moment attempt to respond on the topic of why some “characters” are reported but not considered core to species concepts and others are considered to be fundamental to species concepts.
I hope I haven’t given the impression that I believe one approaches a STABILITY in the set of characters chosen for inclusion in morphological species concepts. Each taxonomic generation (which sometimes is equal to multiple human generations…too few [and decreasing] taxonomists, too many species) has the duty to improve the way the work is done and to do more naming and classifying to improve our knowledge of biodiversity; however, we would be nuts to think that any one of us had reached “perfection” at what we do.
We only need to look back at our mistakes.
We could have dried material, maybe.
The spores of the spring calyptroderma (yellowish to very pallid) are as follows:
[138/7/6] (9.0-) 9.5 – 12.4 (-17.2) × (5.5-) 6.0 – 7.8 (-9.8) µm, (L = 10.6 – 11.2 µm; L’ = 10.9 µm; W = 6.6 – 7.3 µm; W’ = 6.9 µm; Q = (1.35-) 1.40 – 1.77 (-2.18); Q = 1.53 – 1.67 ; Q’ = 1.57).
This is quite a bit different from velosa and from the photograph of spores accompanying the present observation.
For what its worth the volval cap is thicker than it appears in the photo. I have a photo where I was specifically trying to show that. If it does show it clearly, I will try to add it here, or failing that at BAMS. I have also seen robust A. velosa, but never 3 cm in diameter. And don’t forget the very light striations.
I’m not trying to suggest that it IS anything. The jury is still out. Perhaps the dilemma is that this mushroom doesn’t easily fit in to a known catagory, yet you seem anxious to slot it in as a white velosa and willing to ignore any details that might not fit your theory. These little details are what makes this an interesting mushroom. While I do see the similarities, how many exceptions to typical velosa features must there be to suggest that it might not fit the mould?
velosas show more white forms than any other colored amanita that I have observed in the field.
robust forms of velosa are less common, but I have found a few every season. Both velosa and calyptroderma have hollow stipes, whether this feature has been mentioned in other written descriptions or not (it is on the BAMS webpage). universal veils, even within species, come in varying thicknesses. this is hardly the monstrously thick veil of a coccora.
And if this is a coccora, Dude, where’s my membranous and pendulous annulus??!
In my educated opinion, this amanita is just a somewhat unusual but not wholly out of character velosa. The micro fits, the macro fits, and the habitat fits. Geez, what more do we need??!
The features of this mushroom that seems to make a case for it being more similar to spring the time coccora would be the thick, cottony volval patch, much more substantial than A. velosa, and a robust stem 3 cm in diameter, larger than I have ever noticed in A.velosa. It helps to have had it in your hand, and while I know this is a subjective observation, it just has more of a A. calyptrata feel to it. Ritas observations of the hollow stipe also go to A. calyptrata. The striations are very light, not similar to typical velosa or calyptrata.
Having read one of the comments, I would have thought one would be tripping over this mushroom. To suggest that is is commonly found in the east bay is ludicrous. I have lived in the east bay since 1988. Prior to that I spent quite a lot of time collecting mushrooms in the east bay hills, and since it has been my primary area of focus during the mushroom season, especially in the spring between the C. craterellus season, and the morel seasn. This is the first time that I have ever encountered an Amanita like this.
that is inconsistant with Amanita velosa. Variability is the norm.
Here is the draft of my universal veil description for velosa. Note that it’s a draft. There is mention of an internal limb to the volva. It is possible that the ring mentioned by Debbie is the upper part of such a limbus internus that may have had its upper portion stuck to the stem. The circumflexes below are supposed to create a superscript, but for some reason they don’t…even when I remove the quotation marks.
“…universal veil as saccate volva, white on exterior and in interior, palely concolorous with pileus for upper 25 – 50% of limb and whitish below on the inner surface, with limb margin sometimes becoming brownish with age or drying, soft, membranous, persistent, rather tough, sometimes leathery, 1^-^ – 2^+^ mm thick at midpoint between top of limb and attachment to stipe, 26 – 70 × 28^-^ – 46 mm (length measured from stipe base to highest point of limb) and adnate to stipe for two-thirds or more of this distance, with small limbus internus at point of attachment to stipe.”
I’ve add a photo of the inner volva pulling away from the stipe. From my limited knowledge of Amanitas, I don’t think this is a feature that A. velosa shares.
I often find robust examples of Amanita velosa in the East Bay, and white forms are common.
This mushroom has all of the velosa features: hollow stipe stuffed with pith, totally elongating stipe, striate margin, shaggy stipe surface (variable feature, often documented by me), lack of partial veil but with something that we call a pseudo-stipe(a subtle ring of material left as the mushroom expands), and a saccate volva that tapers at the bottom. I look at a LOT of these mushrooms in the field in the East Bay and elsewhere. Check out the BAMS velosa page here:
Hard to say whether it is the same mushroom as the white, exannulate amanita collected in Santa Cruz. And since that amanita, linked to by Ryane, lacks back-up dessicata, inner stipe information and really any sort of in-depth analysis, including amyloidity of spores, who knows? it coulda been a velosa, too.
[70/3/3] (8.7-) 9.1 – 12.0 (-16.3) × (7.0-) 7.7 – 10.0 (-13.0) µm, (L = 9.7 – 11.0 µm; L’ = 10.4 µm; W = 8.5 – 9.1 µm; W’ = 8.8 µm; Q = (1.04-) 1.08 – 1.30 (-1.49); Q = 1.15 – 1.24; Q’ = 1.19).
L = average spore length per specimen examined
L’ = average length for all spores measured
W and W’ are analogous averages for spore width
Q = length/width ratio for single spores
Q = average Q per specimen examined
Q’ = average Q for all spores measured
a_/b_/c = a spores measured from b specimens of c collections
For ranges of values, (m-) n – o (-p) is read as follows: m is the lowest extreme of values seen; P is the upper extreme of values seen; n is the 5th percentile of the values observed; 0 is the 95th percentile of the values observed.
The spores that are in side view are subglobose to broadly ellipsoid. This is the correct shape range for Amanita velosa. The length of cap striations is directly related to cap thickness. A robust specimen can have shorter striations than a “normal” one. The stipe base seems to be like an ice cream cone to me. I associate that with A. velosa.
Dried material would really help.
This collection appears to be quite similar if not the same as the two collections from Santa Cruz (see: http://www.mushroomobserver.org/34466 and http://mushroomobserver.org/33314?search_seq=1379977). I asked David Arora what he thought this might be and his reply was “Have never seen a colored velosa that looked quite like this one so best for now to call it sp. bearing comparison with the Santa Cruz collections. I don’t think of velosa as robust in the way that the spring coccora is, and the collections of this one — if they are the same — have been the size of spring coccora. The striations are less pronounced than in velosa (one Santa Cruz collection was striate on one side of cap but not the other); both collections had an outstanding volva within the volva which pulls away to form a free rim (this tendency much more pronounced than in most coccora or velosa). In many velosa the volva is pinched around the base but this shows no sign of that; the stalk and gills are much more flocculent than in spring coccora.”
Well, with a small amount of trepidation, I’d like to suggest that this might be an albino specimen of Amanita velosa. I’ve personally seen such material at the NAMA foray in the late 1990’s (1998?) that was near Big Sur. Also, I had the chance to visit the Thiers Herbarium at SFSU and look at the collections that Harry and his students called “Amanita alba” and found that all I that had time to check were, in fact, white specimens of A. velosa. So I concluded that at this time of year, the white material from central California belonging to section Vaginatae is quite likely to be A. velosa. This specimen exhibits the rather robust habit of A. velosa, also…hence, my proposal of the name.
Created: 2010-03-14 04:10:01 CDT (-0400)
Last modified: 2013-07-22 16:40:36 CDT (-0400)
Viewed: 540 times, last viewed: 2018-08-14 04:08:06 CDT (-0400)