Hi Ralph, 

I would suggest to compare your fungus to Hymenoscyphus caudatus though I never found it on Beech leaves

Amitiés
Michel

Hi,

this cannot be H. caudatus, because this species has spores with a central depression and are not so scutuloid as shown on the photos.

In my opinion H. caudatus should have spores which are formed in a transition from typically "caudatus-shaped" to the "scutula-shape", which is also shown on several Baral drawings.

regards,
björn

Ok Björn, 
So do you think H. fageolus would be a better proposal. I have here a picture of a collection I called H. fageolus , on Fagus leaf. Spores look more scutuloid, even if some may presnt also some kind of central depression. 

I suppose, Ralph that you noticed paraphyses with VBs , what about croziers ? 

Michel

Hi

I am not sure how variable H. caudatus is. My impression is that it is polyphagous and although it frequently occurs on Populus/Salix, Acer, and Betulaceae, I have also some records on Fagus and Fraxinus.

On Fagus leaves is HB 8350a, and on Fagus cupules 7588c  (see Cubby). But Björn is right, also here the spores are not prominently scutuloid, and show a very slight central constriction.

The constriction is also seen on Michel's photo of fageolus (the valid name is apparently the American albopunctus), which shows big oil drops which are untypical of typical H. caudatus (in my sense). On Ralph's photo a constriction can hardly be seen indeed.

H. fageolus has smaller spores than H. caudatus, though sometimes up to 18. But 20-23 I think is impossible.

Important is also to be sure about the absence of croziers. Rarely I saw collections with croziers. In your case the ascus bases look more like simple-septate.

Zotto

Hello all,

I ooked agian today and concerning the spores I see no central depression. Today I found spores varrying between 18 & 23µm. About 'croiziers', all these ascos  are quite new for me so judging is difficult. Therfore I took some more picture. Hope this helps.

Regards,
Ralph

Wonderful and clear: no croziers.

White (1943) found the asci of the type of H. caudatus to be without. Regrettably his illustration lacks a remark in the legend. The spores in his drawing do not look scutuloid. On the left species the lack of croziers is illustrated (for caudatus this is only mentioned in the text)

Zotto

Merci Zotto for your attention and detailed answer 
Michel

hello,

thank you all for very usefull the information.

regards


Ralph