Looking for fungi on Arundo donax I have found these very small roundish, blackish, inmersed perithecia up to 100-120 microns, more or less arranged in rows and covered by a melanised periderm on dead leaves lying on the ground. Only protruding the roundish papillate necks. The shortly stipitate asci have a conspicuous refractive apical hemiamyloid apparatus (deep blue after KOH-pret.) and hyaline apiospores.

I feel this fungus might belong, or to be near to the genus Pseudomassaria, or into the Diaporthales?.

Have you some idea for help me?

Many thanks in advance

The collection was made at the Botanical Garden of Gijón (north of Spain), at the sea level

Jacques Fournier, 28-03-2016 22:46

Re : Pyreno on Arundo donax with apiospores and hemiamyloid asci

Hola Enrique,
why was I sure you were currently scrutinizing Arundo donax?
Your fungus is very distinctive, I agree with you about Pseudomassaria, or more likely Leiosphaerella because of the very small perithecia.
Did you check Jaklitsch & Voglmayr 2012, Fungal Diversity 52: 75-98? There is not your fungus but sound information on the generic delimitation.
Good luck with your search!

Jacques

Hermann Voglmayr, 28-03-2016 23:24

Re : Pyreno on Arundo donax with apiospores and hemiamyloid asci

Hi Enrique, on Arundo, check for Apiospora montagnei or A. striola...
All best Hermann

Enrique Rubio, 29-03-2016 01:44

Re : Pyreno on Arundo donax with apiospores and hemiamyloid asci

Hi Jacques and Hermann. Thank you for help me. Yes, I had read this paper and, as you say me, maybe Leiosphaerella could be a good genus for it, but I must to search more information about it....Yes, I was not lucky with your fungus on Arundo but I will insist. 

Hermann, my first impression was Apiospora montagnei but I think this genus lacks and apical apparatus at the asci (Hyde & al, Sydowia 50(1): 21-80) and for it I rejected this possibility.