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08-11-2025 00:29

Francois Guay Francois Guay

I found this species in Quebec, Canada, on herbace

04-11-2025 14:53

Josep Torres Josep Torres

Hello.Very small, globose, mucronate perithecia, b

08-11-2025 09:15

Michel Hairaud Michel Hairaud

Bonjour, Pouvez vous m'aider à identifier ce Mol

08-11-2025 12:10

Elisabeth Stöckli

Bonjour, Trouvé sur tiges mortes de Rubus (ronce

06-11-2025 16:50

Rot Bojan

Hello! Yesterday I found a fungus on or near a nee

05-11-2025 11:33

Pierre Repellin

Bonjpur,J'ai trouvé, sur une hampe florale d'Alli

04-11-2025 09:07

Josep Torres Josep Torres

Hello.A suspected Hymenoscyphus sprouting on a thi

04-11-2025 12:43

Edvin Johannesen Edvin Johannesen

Hi! One more found on old Populus tremula log in O

03-11-2025 21:34

Edvin Johannesen Edvin Johannesen

These tiny (0.4-0.5 mm diam.), whitish, short-stip

03-11-2025 19:41

David Chapados David Chapados

Hi,Does anyone knows which genus could this be? G

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Orbilia on Quercus
Chris Yeates, 13-07-2013 13:34
Chris YeatesBonjours tous
venant d'une Angleterre très chaude et très sèche dans la plupart des habitats dans ce domaine . . . . (tout le monde est heureux, je le suis moins!)
I am really determined to try to get to grips with Orbilia from now on and would welcome any help and suggestions during my struggle.

Here is an apricot-coloured collection, found on rather dry decorticated Quercus wood (at a late stage of decay, Nemania confluens close by).


Classic capitate paraphyses (many pigmented) with granular extracellular pigment also (first image).


The asci seem to contain two types of spores (next three images) - I wondered for a long time about Helicogonium but am unsure - are these spores just immature, or aborted, or?


Asci with 'normal' ascospores also present (see last three images). These spores vary from ovoid, through phaseoliform to reniform, so I am thinking Orbilia coccinella / eucalypti (spores small 2.5-3.5 x 1.7-2µm).
Am I well off the mark?


Cordialement
Chris

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Gernot Friebes, 13-07-2013 14:11
Re : Orbilia on Quercus
Hi Chris,

I think this is O. leucostigma/delicatula. Mature ascospores are allantoid and warted (you can see them quite clearly on some of your photos). What you consider normal ascospores on the last three micro photos looks like immature spores to me.

Best wishes
Gernot
Chris Yeates, 13-07-2013 16:36
Chris Yeates
Re : Orbilia on Quercus
Many thanks Gernot
I have so much to learn here and insights like that are priceless; so this represents the mature spore stage then? (right hand ascus).
best wishes
Chris
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Hans-Otto Baral, 13-07-2013 16:48
Hans-Otto Baral
Re : Orbilia on Quercus
Hi Chris
 this is typical O. leucostigma = O. delicatula (= xanthostigma s. auct. p.p.).

Normal spores are consistently reniform (cashew-shaped) and warted. The other seem abnormal spores though inside living asci.

The paraphyses contain in their lower part orange carotenoids, and I assume that the extracellulapr granules escaped during preparation by breaking the cells.

Is it from your home town?

Zotto
Chris Yeates, 13-07-2013 17:09
Chris Yeates
Re : Orbilia on Quercus
Thank you Zotto
collection details are
on very rotten decorticated Quercus branch lying on the ground
Broadhead Clough, near Mytholmroyd, West Yorkshire
53°43'16.79"N  2° 0'13.17"W
207 metres O.D.
12th July 2013
regards
Chris
Hans-Otto Baral, 13-07-2013 18:58
Hans-Otto Baral
Re : Orbilia on Quercus
Thanks. All three asci are mature, I see them all warted, but some spores are in dorsal/front view, others in side view.