25-03-2026 22:23
Marc Detollenaere
Dear Forum,On a debarked stem of Tilia, we found s
25-03-2026 20:53
François BartholomeeusenDear forum members,On 23 March 2026, I found sever
23-03-2026 20:16
Miguel Ángel Ribes
Good eveningI'm unable to identify this Coprotus o
24-03-2026 15:44
Åge OterhalsI hope someone can confirm the name of this collec
25-03-2026 15:06
Bernard CLESSE
Bonjour à toutes et tous,Pourriez-vous me confirm
25-03-2026 10:35
Hulda Caroline HolteHello,I collected this species growing on a dead b
25-03-2026 13:54
Enrique Rubio
Does anyone know where I could download Paoletti's
25-03-2026 15:46
Michel Hairaud
Bonjour, Je sollicite de l'aide pour cette récol
24-03-2026 19:59
William Slosse
Hello everyone,On 23/03/26, I found the following
21-03-2026 15:13
Lepista ZacariasHello everyone, Does any one know of any literatu
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!