Accès membres

Mot de passe perdu? S'inscrire

08-11-2024 17:36

Juuso Äikäs

Recently I posted here my finding of small white a

04-11-2024 17:32

Yves Antoinette

Bonjour, je pense qu'il peut s'agir de Trichoderma

08-11-2024 16:54

David Chapados David Chapados

Hi, I'm looking for help to identify this specime

08-11-2024 15:44

Laurent LENEL Laurent LENEL

Bonjour à tous, ma découverte du jour, une Helve

23-10-2024 17:27

Enrique Rubio Enrique Rubio

Hi againThese tiny apothecia (100-200 µm) were gr

06-11-2024 20:07

B Shelbourne B Shelbourne

• Macro and habitat suggest Hymenoscyphus s.l.,

04-09-2024 21:02

Stephen Mifsud Stephen Mifsud

I have found an interesting Xylaria growing on fal

06-11-2024 11:59

Stephen Mifsud Stephen Mifsud

I am trying to identify a Cheilymenia sp. using ke

05-11-2024 18:00

Karen Poulsen

Hello, Can anyone help with this one? On twigs o

20-10-2024 16:48

Albert Meek

Globose sporesca. 16um, with  many drops. On bare

« < 1 2 3 4 5 > »
Valsa on Prunus spinosa branches
Enrique Rubio, 07-04-2012 19:31
Enrique RubioHello my friends of the forum:

I'd like to know your opinion about this fungus that forms erumpent stromata on Prunus spinosa branches lying on the ground.
Stromatic disc is witish/grayish and the stromata have a conspicuous ventral black line. Spores are hyaline and very heterometrical. Many asci with 8 ascospores. 

We think this is a Valsa species but we have not seen his Cytospora anamorphic state.

Maybe Valsa ambiens?   
Many thanks again
Enrique
  • message #18101
  • message #18101
  • message #18101
  • message #18101
  • message #18101
  • message #18101
Björn Wergen, 07-04-2012 21:10
Björn Wergen
Re : Valsa on Prunus spinosa branches
Hi Enrique,

I also think it should be V. ambiens. See Spielman 1985.

regards,
björn
Enrique Rubio, 08-04-2012 11:30
Enrique Rubio
Re : Valsa on Prunus spinosa branches
Many thanks, Björn
Enrique
Vera Hayova, 08-04-2012 21:09
Re : Valsa on Prunus spinosa branches
Hello,

It can't be Valsa ambiens since there is the black delimitation line. I would suggest it's Leucostoma cinctum.

To make sure, try to do transversal cross-sections of several ascostromata. You can find remnants of the anamorph (usually different in colour) in the upper part of some of them, right in the middle. If it is so, then it is surely L. cinctum. In fact, it already seems so on your pic 1, on the transverse section that is below on the right. This is a distinguishing character of the species, plus your dimensions fit it well.

Hope this is helpful.

Vera
Enrique Rubio, 09-04-2012 18:40
Enrique Rubio
Re : Valsa on Prunus spinosa branches
Hi Vera

What color has the anamorph?   and what are the conidia?. Have you literature or images about this species?

Many thanks for ypur kindly help
Vera Hayova, 10-04-2012 14:17
Re : Valsa on Prunus spinosa branches
Hi Enrique,

Information on this species is limited and very scattered as on many of Valsaceae.

L. cinctum is known to have both anamorph and teleomorph in one stroma. Sometimes, it is easy to notice, even without a cross section, like on photo 1 where pycnidial ostiole is clearly seen surrounded by ascomatal ostioles. In this case, conidioma remains inside there, although appearing rather unusual (photo 2) but conidia still can be found there; they look like tiny ascospores. At a later stage, when perithecia have mature asci, normally one can see only remnants of the anamorph as a greyish mass.

Vera

PS. Pictures taken also on Prunus spinosa.
  • message #18125
  • message #18125
Enrique Rubio, 10-04-2012 14:47
Enrique Rubio
Re : Valsa on Prunus spinosa branches
Thank you Vera
Do you know what are morphologically the conidia and its measures?
Vera Hayova, 10-04-2012 15:25
Re : Valsa on Prunus spinosa branches
Conidia are similar in shape to ascospores but much smaller - allantoid, hyaline, about 6-7 x 1.5 mkm.
Enrique Rubio, 10-04-2012 18:01
Enrique Rubio
Re : Valsa on Prunus spinosa branches
Dear Vera:
Unfortunately I could not have found anamorphe remains.

Many thanks for you help
Enrique
Vera Hayova, 10-04-2012 18:36
Re : Valsa on Prunus spinosa branches
Hi Enrique,

Anyway I think it's L. cinctum, due to asci/ascospore dimensions. You probably have all mature ascostromata and it's too late to see anamorph.

Best wishes,
Vera
Enrique Rubio, 10-04-2012 18:48
Enrique Rubio
Re : Valsa on Prunus spinosa branches
OK., Vera.
Next week end i'll try to collect more material and I will looked for the anamorphic state on more branches.
Many thanks!
Enrique
Vera Hayova, 10-04-2012 18:55
Re : Valsa on Prunus spinosa branches
OK, good luck. Let me know if you find it. I believe this feature of the species should be everywhere the same.