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13-09-2025 14:10

Wim de Groot

We found this hymenoscyphus on rubus fruticulosis.

13-09-2025 15:43

Edmond POINTE Edmond POINTE

Bonjour Christian,J'ai trouvé deux spores ressemb

11-09-2025 16:57

Jason Karakehian Jason Karakehian

Our revision of Marthamycetales (Leotiomycetes) is

13-09-2025 14:01

Thomas Flammer

dark brown apothecia, splitIKI-Spores biguttulate

10-09-2025 23:53

Marcel Heyligen Marcel Heyligen

Found on Robinia pseudoacasia together with Diapor

10-09-2025 17:18

Blasco Rafael Blasco Rafael

Hola, encontre este estiercol de vaca estos apotec

02-09-2025 11:34

Thomas Læssøe

https://svampe.databasen.org/observations/10527903

07-09-2025 08:19

Josep Torres Josep Torres

Hello.Tiny pinkish discomycetes, photographed and

09-09-2025 12:07

Edmond POINTE Edmond POINTE

Bonjour amis mycologues,Trouvé sur moquette de ch

08-09-2025 19:07

ruiz Jose

Hola me pasan esta recolecta en madera de fraxinus

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Dothideomycete on Phalaris culm
Nick Aplin, 25-04-2014 02:39

Salut à tous,


I am trying (and mostly failing!) to identify some ascomycetes in a floodplain in the South of England - I wonder if anyone can help me with this species on a dead Phalaris culm?


Collected 24/04/2014


Perithecia: Mostly immersed (some almost erumpant), 0.5 - 0.6mm diam. All ostioles rounded


Asci: Bitunicate, 8-spored


Ascospores: 5-Septate, brown and distinctly roughened on release, 26.8 - 30.6 x 6.1 - 7.2 µm. No sheath observed in indian ink


Pseudoparaphyses: around 2 µm diam, mostly unbranched, septate, without conspicuous droplets


There was an anamorph nearby which reminded me of Stagonospora (?)


I've tried looking in 'the usual' genera that I associate with grasses in this habitat (Massarina, Phaeosphaeria, Lophiotrema, Massariosphaeria etc.) but with little luck yet - Can anyone make any suggestions or at least point me in the right direction?


Amitiés,


Nick

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Björn Wergen, 25-04-2014 05:47
Björn Wergen
Re : Dothideomycete on Phalaris culm
Hi Nick,

my first thought was that the species belongs in the group of Phaeosphaeria luctuosa, which has a Stagonospora anamorph. This anamorph should have longer conidia as shwon on your third picture. The spores of Ph. luctuosa are furthermore described as being smooth (Leuchtmann 1984).

I do not know your species, but I have collected and studied many of these small dots on grasses and herbs. I do not wish to disturb you with sending another species :D

regards,
björn
Nick Aplin, 28-04-2014 01:25
Re : Dothideomycete on Phalaris culm

Hi Björn,


Thanks, I also thought of Phaeosphaeria at first, but was thrown off course by the spores which seemed quite lophiostomoid when immature (sorry for the poor photo).


I went back over Shoemaker & Babcock and didn't find anything that fit, though Montagnula subsuperficialis seemed very close. The authors mentioned a similar species which seems a good solution for my problem: Montagnula rhodophaea.


What do you think?


I noted that Leuchtman only described microconidia as an anamorph for this species, so perhaps my Stagonospora belongs to another fungus......


I have almost exhausted the specimen, so I would probably be wasting your time by sending this one - If I collect it again I'll post it.


Best wishes,


Nick

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Björn Wergen, 28-04-2014 05:56
Björn Wergen
Re : Dothideomycete on Phalaris culm
Hi Nick,

I think you are right, finely dotted spores are typical for Montagnula species, but also for some Leptosphaeria and Phaeosphaeria, so we have to look for hyphal structures on the surface, something like a "Stroma" or a Clypeus. A section through the pseudothecia would also help.

regards,
björn
Nick Aplin, 29-04-2014 01:05
Re : Dothideomycete on Phalaris culm

Hi Björn,


There are indeed patches of dark stromatic tissue around the pseudothecia, and surface of the host (under the epidermis) is black with fungal cells. It seem there is also a golden-red discolouration of the substrate which I think Leuchtmann describes (my German isn't very good and Google Translate doesn't help much sometimes!).


The pseudothecium wall seems OK too - I think I will label this one as M.rhodophaea unless anyone disagrees....


Best wishes,


Nick


 


 


 


 

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