20-12-2025 23:08
Patrice TANCHAUDBonsoir, récolte sur sol sablonneux dans l'arriÃ
21-12-2025 09:32
Josep Torres
Hello.A tiny ascomycete found embedded in wood in
20-12-2025 15:47
Mirek GrycHi.These grew on pine wood that was heavily covere
18-12-2025 21:17
Pol DebaenstThe identification took me to Byssonectria deformi
15-12-2025 07:09
Danny Newman
indet. Rutstroemiaceae sp. on unk. fallen leavesMc
19-12-2025 10:10
Patrice TANCHAUDBonjour, récolte réalisée en milieu dunaire, a
18-12-2025 17:23
Bruno Coué
Bonjour,je serais heureux d'avoir votre avis sur c
18-12-2025 18:07
Margot en Geert VullingsThese plumes were found on rotten wood.They strong
Hi to allThis fungus forms subcuticular pseudothecia (¿?) under the periderm of stems of Arundo donax. These pulvinate and ostiolate ascomata, arranged in longitudinal lines, are singly or situated on small stromata with some other ones, 0.4-1.5 mm long, up to 0.15 mm high.
The 8-spored asci are cylindrical and I think they are bitunicate altough I can see maybe a small structure near the apex. The golden brown bi-cellular ascospores and the pseudoparaphyses are showed in the pics. I tough could be a Didymella or a close related genus, but I don't know a good genus for this collection.
Have you some ides for it?
Thanks again
not sure but your fungus looks like a Roussoella. If so the spores should be delicately longitudinally ribbed, it's difficult to see if the preparation is not very thin.
The smaller spores with broadly rounded ends would fit R. donacicola (Speg.) Ju, Rogers & Huhndorf which is common on this host. The slightly larger and more narrowly elliipsoid are less typical of this species and recall a tropical species, R. chiangraina (in Phytotaxa 181(1), 2014).
Saludos,
Jacques
Hi Jacques
Fantastic! I feel you are right, although the faint striate ornamentation is hardly visible. But the rest of the generic characters fits well with this fungus.
Thanks a lot!