Accès membres

Mot de passe perdu? S'inscrire

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

04-11-2025 14:53

Josep Torres Josep Torres

Hello.Very small, globose, mucronate perithecia, b

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

28-10-2025 15:37

Carl Farmer

I'd be grateful for any suggestions for this strik

03-11-2025 16:30

Hans-Otto Baral Hans-Otto Baral

Hello I want to ask you if you have found this ye

01-11-2025 09:14

Francis Maggi

Bonjour,Trouvé sur Xanthoria parietina à Valdebl

28-10-2025 19:33

Nicolas Suberbielle Nicolas Suberbielle

Bonjour à tous,Je voudrais votre avis sur cette r

« < 1 2 3 4 5 > »
Microthyrium on Bark of Hedrea helix
Peter Thompson, 01-05-2013 13:47
Hello Everyone,

I recently found a Microthyrium species with evenly coloured thyriothecia growing on the bark of ivy (Hedera helix). It is quite clearly not Microthyrium ciliatum var. hederae, usually found on leaves, because the spores are significantly larger.

I have attached an image of the fruit bodies and the microscopy.

I wonder if anyone has an idea as to which species it will be.

Thank you,
Best wishes,
Peter.

  • message #23209
  • message #23209
Chris Yeates, 01-05-2013 15:40
Chris Yeates
Re : Microthyrium on Bark of Hedrea helix
Hello Peter
that doesn't look right for a Microthyrium to me . . .
cheers
Chris
Peter Thompson, 01-05-2013 16:38
Re : Microthyrium on Bark of Hedrea helix
Hello Chris,

The fruit bodies are flat and can be lifted intact off the surface of the host. They are surely thyriothecia of Microthyrium or a similar genus.

Best wishes,
Peter.
Chris Yeates, 01-05-2013 19:01
Chris Yeates
Re : Microthyrium on Bark of Hedrea helix
Hello Peter
I wouldn't argue with "similar genus" and it may be that the photo is somewhat deceptive, but is the upper surface really only one cell thick?
Chris
Alain GARDIENNET, 01-05-2013 20:48
Alain GARDIENNET
Re : Microthyrium on Bark of Hedrea helix
Hi,
Yes perhaps another Microthyriaceae, like Phragmothyrium flageoletii (just an idea to check).
It woulb be useful to see a vertical cut, and the structure of peridium.
Alain
Peter Thompson, 26-05-2013 19:02
Re : Microthyrium on Bark of Hedrea helix
Hello Alain,

Thank you for your suggestion of Phragmothyrium flageoletii and my apologies for taking so long to respond.

I have found a document of Illinois Biological Monographs. Using the key to genera, I arrive at Phragmothyrium as the genus. From the species listed and described, only two are known to grow on Hedera. P. flageoletii is certainly the closest from the sizes of spores and asci, but I also see paraphyses, whereas the Illinois Biological Monographs describe the species as not having paraphyses.

I have attached the cross section, which you requested (with thanks to Peter Wilberforce, who is also interested in this sample). Also attached is the image of the asci.

We wonder what you think?

Thank you,
Best Wishes,
Peter.

  • message #23646
  • message #23646