28-03-2026 07:55
Marc Detollenaere
Hello everybody,Yesterday I found a number of whit
26-03-2026 15:31
Ã…ke Widgren
Hello,I found this one in October last year, on r
27-03-2026 15:23
Gernot FriebesHi,this Trichopezizella deviates from typical T. b
25-03-2026 10:35
Hulda Caroline HolteHello,I collected this species growing on a dead b
27-03-2026 15:08
Gernot FriebesHi,I'm looking for help with this coelomycete on C
27-03-2026 10:47
Ã…ge OterhalsI have tentatively identified this Stictis to S. f
24-03-2026 21:37
Elisabeth StöckliBonsoir,Sur bois (tronc) très pourri de conifère
25-03-2026 22:23
Marc Detollenaere
Dear Forum,On a debarked stem of Tilia, we found s

Bonjour chers collègues,
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aujourd'hui j'ai ramassé un Nectria s.l. sur Hypoxylon fragiforme, que m'etonne par ces charactèrs que je ne connais pas (ce que ne veut dire beaucoup, car je connais des Nectrias assez mal ....)
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Les spores sont assez petit, appr. 8-10 µm de longeur, verruculeuse.
C'est pas Nectria episphaeria, parce-que les perithecia ne sont pas papillé, mais avec une sommet applati.
Voici des impressions sur cets perizhecia.
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peut quelqu'un me donner un piste pour cet espèce, ou me instruire que je doit examiner en plus?
merci beaucoup,
Andreas
I bet this fungus is Cosmospora arxii. The apex of the perithecia does puzzles me a bit, though. The perithecia of specimens that I have seen of C. arxii have had blunt apices. I think it must be a morphological variant of the same species. You can confirm the identity of the fungus by isolating it into pure culture. It should have a salmon-pink colony on potato-dextrose agar.
Best,
Cesar Herrera
Dear Cesar,
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thank you very much for your tentative identification.
Unfortunately I have no possibility to make a pure culture of it. Is there something else to verify the identification? How certain is it that I can put the name arxii to it?
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thank you again,
Andreas
Hi Andrea, hi Cesar.
Cesar, could you send me a complete description of C. arxii please.
This fungus is very current in our countries.
Alain
Andreas, if you want I can try a culture from your specimen. I am interested because there are two species occuring on H. fragiforme. One with a pink-salmon colony and another with a green colony.
Regards,
Christian


