Hola, Miguel Ángel. Creo que no ha entrado el adjunto.

Saludos,

Tomás Illescas

Gracias Tomás, creo que ya está solucionado.

Un abrazo,

I think there is no doubt: Peziza saniosa.
Ciao

From your photos I am quite sure you included living asci in your measurements which are much longer than htose dead asci in the literature.
Zotto

It would be useful to know in which moment of his life was measured the lenght of an ascus...!
he he he

Of course, asci should be measured in the mature stage, in this Peziza when the spores are ornamented. I feel that some measure also immature asci, and dead and livng mixed, so then you have a big scope of length and width, and little reliability

Zotto

Thank you Mario, Zotto

Since I am in this forum I am learning more and more about the vital taxonomy, and I am trying to do all my measures through photos in water with living material. But this have a little problem, not at all previous literature has made the description and measures in the same conditions, so the comparison is difficult, especially for me because I have not a great experience.

About P. saniosa, indeed, IKI asci are shorter than water asci.

Best regards

IKI not only kills cells, but in the same moment the asci came in a medium with IKI, the mature and also the submature ones explodes releasing the spores. So if your measurements are made in IKI, you lose all the longer asci and the mean value will result much shorter.
But the length of a single living ascus varies considerably also when the spores seems mature yet: if you observe the hymenium in sections (without pressure on the coverglass) you will see many asci with mature spores remaining "submerged" under the paraphyses. Only a few (those really read to shoot the spores) exceeds the paraphyses tips. This final elongation can significate 40-50 or more microns, and immediately after the spore discharge the ascus returns considerably shorter.
So I think it is better to measure asci in an hymenial section. They all reach the same level between the paraphyses, so the length variation is due to the different level from which the single ascus arises from the subhymenium. Hymenium is thinner towards the margin of the apothecium, and usually thicker towards the center, meaning that the length varies in the different positions.
Substantially, the length of every ascus is perhaps due to accidental factors. And the observations in literature are affected by the problems you (both Zotto and Miguel Angel) pointed out. That's why I think it's better to spend our time to measure more spores (or to collect more material on the ground!!!); the mean length of asci is easily estimated simply measuring the thickness of the hymenium.
I wait for some... reaction (!?)

A great and interesting lesson, Mario; the only problem is to be able to make a good and thin slice without microtome. I am not very skilful with my hands.

Thank you

I have never used a microtome, and I never heard of microtome sections showing living elements. Generally, the procedure (e.g. freezing) kills the asci, as I suspect. So I recommend to use razor blades under the binocular, which is usually no problem if the apos are not too small or not too long-stalked.

Well, I am happy, Mario, that you are so skilled with the shrinking effect. I often have to teach it, and some persons still have doubts about it.

I am conform with you that ascus size is quite variable, often a bit smaller towards the margin, and different between different populations. Anyhow I think it is valuable to measure asci. In Orbilia we need as much data as possible, because in many cases we have difficulties to decide which collection we should include in a species and which not, so sometimes ascus size helped here. And I concur that we must consider increase in size shortly before explosion. Especially in asci with a jack-in-the-box this problem is obvious, but also Orbilia asci elongate a good deal, and I differentiate therefore between normal and full turgescence here. In addition, I separately evaluate the dead asci. But I never note every measured value separately as is frequently done.

So, when I see ascus measurements without a statement to living or dead, I first look at the pictures and then assume that the data refer to the figured state. If no such reference is possible, ascus size data are of no use at all.

To measure the hymenial height is not always easy because a subhymenium is not always clearly delimited, and it is then necessary to see the ascus bases. The asci in Orbilia have often rather long stalks ending at different levels at the base of the hymenium or even in the subhymenium, when viewing a section. In my experience it is quite difficult to say where the subhymenium begins, but it is clear where the ascus base ends. Although such stalked asci are not easy to trace down, I use the following method: living asci are most often quite clearly to trace to their basal septum, while dead asci can be stained with IKI or MLZ and are then very clearly seen in the context of the section.

Zotto

I keep a certain paper ("vital versus herbarium taxonomy...") on my bedside table, with the Holy Bible, Zotto.
From my little corner (study of Helvella) I share your conclusions about that.
But I am not very experienced about many genera of ascomycetes, and Orbilia is one of them.
I know it's frequently difficult to see the limits of sybhymenium, but if possible, we'll see that his thickness is (roughly, but not much!) equal to the variation in length of the asci. Obvious!
I think it's less error on so doing, rather that to prepare a "squash" mount of the hymenium and to measure the asci without any possibility to understand the "living stage" of every ascus.
Whenever it's possible, of course.
Miguel Angel, I think in Peziza is quite simple to make hand sections, because the apothecium is not too small, the consistency of the flesh is suitable, and the cells are rather big so you don't need a very thin section.
Try this way on your Peziza:
1) use a new and sharp razor blade
2) make a tangential strip of apothecium, including the margin at one side, about 5-6 mm of length(parallel to the margin) and 2-3 mm of width (radially). From bigger fragments, cutting is more difficult.
3) on the micro glass, hold the fragment lengthwise with the index finger (1).
4) with the other hand take the razor blade resting flat onto the finger (1) and cut gently.
5) throw away the first fragment cutted, and then cut slices always with the side of the blade in contact with the finger (1). The finger (1) with his little movements will determine the thickness of slices.
6) the sections (slices) will remain mostly attached on the side of the razor blade.
7) transfer the sections by contact on a drop of water onto a micro glass, using a needle.
8) choose the best sections and remove the others.
9) put the coverglass and observe the best thin sections you never made!
I hope I was intelligible enough. Let me know.

Thanks Zotto, Mario

Wonderful and didactical explanations. I must learn so much... Mario, I think I have understand your procedure, but now I haven't any fresh Peziza or similar to try it. Sure, this weekend I will find someone, so next monday I will practice it.

One question for both, do you usually observe the section in water or it depends of the genera?

Tranks,

Hi Miguel & Mario

I always put a section in water, even if I study dead herbarium material, e.g., in order to be able to test the IKI reaction. Dead sections I soon treat with KOH after IKI, to inflate the cells and get a clearer image, while living sections I study in water (they yield a much more clear image than dead KOH preparations), and only at the end I use chemicals, depending on the genus (e.g., Mollisia for the yellow KOH-reaction).

Zotto