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Michel Hairaud Michel Hairaud

Bonjour à tous/Hi to everyone I am passing along

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François Freléchoux François Freléchoux

Bonjour,Peut-être Mollisia palustris ?Trouvée su

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Danny Newman Danny Newman

Melanospora cf. lagenaria on old, rotting, fallen

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Johan Boonefaes Johan Boonefaes

Unknown anamorph found on the ground in coastal sa

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Small clavate hairs, negative croziers and IKI bb

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indet. Rutstroemiaceae sp. on unk. fallen leavesMc

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Good evening, On 12/11/2025 I found ascomycetes w

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Pseudosclerococcum golindoi (det: Zotto)near Cosb

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ITS sequences from the following two collections B

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indet. Rhytismataceae on oak leafnear Purchase Roa

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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.