Betula seeds have wings, Alnus seeds apparently not, but the wings may sometimes disappear when a Ciboria grows on them.

My feeling is, when I look at my folders, that spore shape is different, apart from slightly longer spores in C. seminicola. Your spores fit much better C. betulae. But I have seen very few samples of C. seminicola, so maybe the difference is accidental.

With molecular data the matter of species distinction is not yet explored, I only know of sequences from C. betulae. So whether the two taxa are really distinct is not clear to me.

Hi Zotto,

the possible loss of the seed wings was the main reason why we doubted the safe determination as Ciboria seminicola. Thank you for your opinion that approves these doubts. I'm curious of what future sequence analyses will show.

Vielen Dank und beste Grüße
Jan-Arne

Hi Jan-Arne and Zotto,

concerning the seed: can Carpinus betulus be excluded? By size it could fit well (using the diameter of the apothecium as a scale).
Here is a random internet picture:
http://info.sotvorenie.kiev.ua/content/family_estate/plants/kinds/trees/carpinus_betulus/carpinus_betulus_big18.jpg

Regards
Martin

Indeed, Martin we never know. We let us guide from the literature, and there is no Sclerotiniaceae on Carpinus seeds, as far as I remember....

There is Sclerotinia carpini on Carpinus seeds. Has someone the protologue by Klika 1923 in Casopis Národního muzea Praha 4?

Regards
Martin

there is a good chance that this is the right quotation:
KLIKA J. E. (1923): Príspevek k ceské mikroflore — III. Cas. Nár. Mus. 97: 95—99

Hello Martin,
tomorrow I'm going to the library, I'll try to find it and make a copy of that article. 
Viktorie

Hello,

the quotation is correct. Along with the previous 2 parts, the article gives a list of some fungi collected in central and east Bohemia with main focus on rusts and mildews. 
Description of S. carpini (the only new taxon in these 3 articles) is on p. 98, unfortunately he doesn't cite the type specimen nor exact collection date. I'm not sure which museum has his herbarium, maybe PRM or PRC (since 1922 he was working on Czech Technical University in Prague, since 1951 professor of botany on Charles University where the PRC is located).

The text in czech says: "In the vicinity of Prague (Radotín, Karlštejn [?]) and in alluvium of Labe / Elbe (Sadská), in groves, this september and october, everywhere very abundant. Hornbeam nuts are changed to sclerotia from which the fruitbodies grow on more or less long stalks. I didn't have the opportunity yet to study their development."

Viktorie

many thanks for this!
It is difficult to make up one's mind with such a short description without pictures. But My guess is that it is Hymenoscyphus fructigenus va.r carpini.

The heteropolar spores and the mention of 3 guttules point there, also the long stalk.

Zotto

Thank you very much Viktorie!

And I follow Zotto's interpretation.

Regards
Martin

Hello everyone,

that was some interesting new information. From my point I can only say that I don't think Carpinus betulus grew anywhere near the location, Alnus did at least in a certain distance, while Betula was quite close. And I certainly agree with Zotto's interpretation as well.

Best regards,
Jan-Arne