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11-02-2012 06:50

Roland Labbé

Bonjour !  Voici une planche et une photo macro

24-07-2024 14:07

Elisabeth Stöckli

Bonjour,Cette espèce a été trouvé sur place à

23-07-2024 19:27

éric ROMERO éric ROMERO

Bonjour, Je n'ai pas d'idée pour cette espèce t

24-07-2024 13:19

Thomas Flammer

I am looking for a PDF of the above article. Thank

22-07-2024 10:20

Hans-Otto Baral Hans-Otto Baral

Hello please note that I uploaded today an Englis

21-07-2024 10:13

Thierry Blondelle Thierry Blondelle

Bonjour,Récolte sur branchette de Castanea dans u

19-07-2024 10:24

Kozak Robert

Date: 2024.07.16Loess gorges, on soil with a lot o

21-07-2024 10:28

Alan Rockefeller Alan Rockefeller

Which Peziza did I find on horse dung in Humboldt

19-07-2024 11:08

Miguel Ãngel Ribes Miguel Ángel Ribes

Good morningThis Scutellinia from July 9 grew at 1

21-07-2024 06:23

Masanori Kutsuna

Dear all, Does anyone have these papers and send

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Melanomma?
Hans-Otto Baral, 20-08-2010 13:11
Hans-Otto BaralHi

In Middle-Sweden (Saxnäs) grew a bitunicate pyreno on Sorbus aucuparia standing branch together with Orbilia aristata etc. I compare ist with Melanomma but the spores are hyaline, apparently they are ejected when 1-septate, but get more septa when older, still remaining hyaline. Many perithecia are overmature but some are o.k.

Zotto
  • message #12527
Hans-Otto Baral, 20-08-2010 13:14
Hans-Otto Baral
Re:Melanomma?
1-septate Spores ca. 15-18 x 6-6.5 µm, overmature 17-23 x 7-8.5 µm
  • message #12528
Hans-Otto Baral, 20-08-2010 13:15
Hans-Otto Baral
Re:Melanomma?
The small tree was dead because of too much shade.
  • message #12529
Hans-Otto Baral, 23-08-2010 10:03
Hans-Otto Baral
Re:Melanomma?
Section of perithecium
  • message #12550
Hans-Otto Baral, 23-08-2010 10:04
Hans-Otto Baral
Re:Melanomma?
near ostiole
  • message #12551
Hans-Otto Baral, 23-08-2010 10:06
Hans-Otto Baral
Re:Melanomma?
perithecia attached by a short stipe
  • message #12552
Hans-Otto Baral, 07-09-2010 22:54
Hans-Otto Baral
Re:Melanomma?
I've sent my images to Walter Jaklitsch, and he has an idea:

"I collected this fungus several times on about 10 different, unrelated hosts including Spiraea. Some of my specimens were examined by Andre Aptroot, who determined them as Dothidotthia ramulicola (Peck) M.E. Barr. I think one of them was also confirmed by Barr as this fungus. I do not think that they were right, because Dothidotthia has broad, nearly ellipsoid asci with biseriate ascospores, while Otthia has cylindrical asci with uniseriate ascospores, similar to your specimen, where perhaps the spores are not strictly uniseriate.

Anyway, I think that your fungus is Otthia spiraeae (there may be several species hidden under this name ??), immature and aberrantly developed. It seems that ascospores develop very slowly in this species and that unfavourable conditions disturb their development, leaving them in a certain stage without chance of maturing. When mature, ascospores of Otthia spiraeae are about (17-)21-28 x 11-13(-15) µm, very dark brown, 2-celled, with or without various combinations of delicate secondary septa; the 2 cells may be grossly muriform; when hyaline they are 16-23(-25) x 7-9 µm and also develop quite strange combinations of septa, as you show in one of the images. I collected specimens with hyaline ascospores from December to April, so this kind of development may be correlated with low temperatures, or let´s say development is retarded or stopped by low temperatures (?).

Also the ascomata in your images are exactly what I have seen, often with a pallid or dark and stellate ostiolar area in the same specimen.

Interestingly, Barr descibed additional/secondary septa for D. ramulicola
and also ascospore size (of the hyaline spores) fits better. So, in absence
of an anamorph, and if the asci may not be so important, one could also
think of D. ramulicola."