Micro fungi

[fairplay]

I see another book ? coming out before long.

Neil.

[Chris Yeates]

Originally Posted by stickman

. . .


So with the help of a couple of websites (Nice one, Stip) and a check of the FRDBI for substrate fits, I've come to the conclusion this is Arachnopeziza obtusipila.

Any comments welcome as always!

Cheers, Nick

hi Nick

superb drawing . . . . running this through Korf's Monograph of the Arachnopezizeae in Lloydia Vol. 14 part 3, pp. 129-180 it would seem to come down to either A. obtusipila or the not (yet!) British A. delicatula; key characters would appear to be how the spores lie in the asci and spore septation:
" . . . . Ascospores. . . . . irregularly biseriate, 3(4)-septate at maturity . . . . " for A. obtusipila and:

"Ascospores. . . . . in a parallel bundle or irregularly multiseriate, 3-5-septate at maturity" for A. delicatula

your drawing would suggest the latter . . . . .

Chris

[Stip]

Hi Nick,
Very nice drawing!! The asci are mature and in full turgor so the arrangement of the spores in the asci are not compareble with literature descriptions made of dead material, in full turgor asci the spores are in inoperculate discos mostly all pushed up before discharging.I suggest you kill the cells by boiling the slide shortly with a lighter or so (you probably don't like what you see than, I don't!) for comparisation with literature.
But I agree with Chris it looks a lot like delicatula too, the best destinctive characters are the spore septation and dimensions (L/W ratio).
24-40(48)x 2-2,7(3,4) , 3-5 septate for delicatula
16-30x 2,7-3,4 , 3-4 septate for obtusipila
If you like you can download the full article here to see the full descriptions for yourself: http://helotiales.nl/doorgeefluik/Ar...monog-Korf.pdf
cheers,
Stip

[stickman]

Thanks for the input, Chris.

Never easy, is it?

Does Korf mention what mountant is used for the monograph and if living specimens were studied?

I ask because I noticed that the spores are biseriate in old (dried) material plus whenever I mounted in Cotton Blue or Lugol's but the asci became inflated with the spores more irreguarly arranged at the top of the asci in living material mounted in water.

I have a several (rather poor) photos of spores suggesting more than 3 septae, this one mounted in Lugol's:



Anyway, I now have a niggling feeling that I've misinterpreted what I've been seeing (some of those septae are pretty ambiguous - perhaps I should have drawn them in grey?) so back to the 'scope, and perhaps the drawing board too.

Cheers, Nick.

[Stip]

I ask because I noticed that the spores are biseriate in old (dried) material plus whenever I mounted in Cotton Blue or Lugol's but the asci became inflated with the spores more irreguarly arranged at the top of the asci in living material mounted in water.

Hi nick,
the living spores don't become inflated in water mount but they shrink due to the loss of cell turgor in lethal mounts as well as the asci.
The spore arrangement in literature is in my opinion mostly neglectable because most descriptions are made of herbarium material and the arrangement depends fully on the ripeness of the fruitbodies at the time of drying and the drying speed. Exceptation are species with spores almost as long as the asci and with round spores
cheers,
Stip

[Chris Yeates]

Originally Posted by Stip

. . . . .
The spore arrangement in literature is in my opinion mostly neglectable because most descriptions are made of herbarium material and the arrangement depends fully on the ripeness of the fruitbodies at the time of drying and the drying speed. . . . .
cheers,
Stip

at the BMS Ascomycete Workshop this spring we all had this truth stressed to us by that great advocate of 'vital taxonomy' Zotto Baral . . . . .

the tradition of using herbarium material as the basis for studying fungi (particularly discomycetes) was unfortunately one long-maintained in Britain - George Massee in his British Fungus Flora Vol. IV, p. 4 writes:
"Boudier, a French Mycologist, has proposed a classification of the Discomycetes, based on the mode of opening of the apex of the ascus; the arrangement , however, has not been adopted, as the character can only be distinctly observed in the fresh specimen."

and again (on pages 8-9):
"When it is desired to make a thorough study of the morphology of a species, it should first be placed in alcohol, and allowed to remain for some days at least. By adopting this method the specimen is rendered firm, and the whole structure at the same time made quite clear. When collecting, it is always advisable to carry a bottle containing methylated spirit, into which specimens intended for critical examination can be placed. These can afterwards be placed in absolute alcohol, or will work quite well if only kept in methylated spirit, and in this medium they can be kept for any length of time—the longer the better—before being used." (my underlining - C.)

in other words - kill it in the field - Zotto would throw his hands up in despair

Chris

[Chris Yeates]

Originally Posted by stickman

I have a several (rather poor) photos of spores suggesting more than 3 septae, this one mounted in Lugol's:



Anyway, I now have a niggling feeling that I've misinterpreted what I've been seeing (some of those septae are pretty ambiguous - perhaps I should have drawn them in grey?) so back to the 'scope, and perhaps the drawing board too.

Cheers, Nick.

hi Nick

try Congo Red and Cotton Blue / Lactophenol as well . . .

Chris

[stickman]

Originally Posted by Chris Yeates

hi Nick

try Congo Red and Cotton Blue / Lactophenol as well . . .

Chris

After hours of deliberation (and lots of slides) I feel I have P.obtusipila.

It is clear that what I originally thought were extra septae were, in fact 'striations' brought about by the coalescence of oil droplets within the spore. This occured both in Lugol's and Cotton Blue- it was only with Chris' suggestion of Congo Red (a stain I hardly ever use with ascos for some reason) that the situation became clear.

My spore sizes of 23-30 x 2.5-3.5 µm (measured in water) suit for this species too.

Well, if nothing else I have learnt that different mountants can have various (often destructive) effects on morphology, and the only way ahead, at least for illustrative purposes, is to prepare as many slides as possible, using as many different stains & reagents as one can possibly lay their hands on!

For clarity, I will try to sketch the spores again tomorrow to show exactly the effect that Lugol's/Cotton Blue had on the spore's interior - It may help others to avoid making the same mistake.

Thanks for your help, Nick.

[Stip]

at the BMS Ascomycete Workshop this spring we all had this truth stressed to us by that great advocate of 'vital taxonomy' Zotto Baral . . . .

I am one of that firm too

Good luck with it Nick

Stip

[Lancashire Lad]

Sphaerosporella brunnea?

Found yesterday on damp charcoal remains of a woodland fire site that is now being colonised by mosses.

Growing in large numbers, generally a few millimetres apart, on many of the individual bits of charcoal. - But there were a few tightly packed groups of four/five fruitbodies as well.

Some were flat/saucer like, some were slightly raised at the margin giving a shallow dish appearance.

Sessile, outer surface covered with appressed/adpressed tufts of hairs, and lines of shorter pointed hairs around the margin of the disc.

The one in the photo is 2.5mm across, but the largest found were 4-5mm across.



Microscopy details: -

8 spores to each ascus. Spores were all spherical, almost colourless measured between 12.5micron and 15.2micron, the majority having one large guttule each.
Long thin paraphyses (slightly longer than the asci), broadening very slighty at outer end.

Marginal hairs (showing as a translucent brown colour under the scope), blunt at the inner end, tapered to a point at the outer end, each generally being divided into two or three cells. (bi/tri septate?).

Any confirmation/ other suggestions much appreciated.

Regards,
Mike.