Hi Bernard,

yes - strange.

You say the inside is powdery, without fungal structure? Can you give a foto of the microscopical investigation?

You say there can be no insect found, nor larvae. So a fungus is quite likely (but possible also virusses or bacteria). I think of Protomyces or something similar, but this does not fit fully, macroscopically.

Without details of (fungal) microscopical structures I think you won`t find help here (?).

Best regards, Lothar

 

 

Bonjour Bernard,

As tu écarté l'idée d'un myxomycète à l'état de plasmode avancé mais pas encore mature ?

Michel 

 

Merci Lothar et Michel pour vos interventions. Je reprends l'observation de cette curiosité demain soir et vous tiendrai au courant !

Amitiés,

Bernard
_____________________

Thank you Lothar and Michel for your interventions. I resume the observation of this curiosity tomorrow night and will keep you informed!

friendships

Bernard

Hello Bernard,

could it perhaps be a Taphrina? Some species occur also on flowering plants (T. potentillae), maybe there's a species on Asteraceae as well. 

Best regards,
Viktorie

Hello Victorie,

as far as I know no Taphrina ist known on Asteraceae (see Klenke & Scholler), but on Protmycetaceae (Taphrinales), as I wrote above. But, The macroscopical appearance is not typical for this, and no species is known on Lapasana (as far as Klenke & Scholler have seen every publication ...).

Best regards, Lothar

Hi Lothar, Michel and Viktorie,

Here are some microscopic pictures. Apart from some round corpuscles (refractive crystals?), I do not see any hypha or structures that remind me of a mushroom ... I do not think it is a myxomycete.

Bernard

Bonjour Nicolas,

Je suis content de te lire car c'est finalement cette impression-là que j'avais car comme tu l'as remarqué, on voit d'autres petites "gouttelettes" solidifiées. Pour moi aussi il s'agit de latex solidifié et on pourrait imaginer par exemple un insecte piqueur-suceur (Hemiptera) responsable de l'écoulement du latex (typiquement présent chez les Astéracées Liguliflores) et vu les températures caniculaires des derniers temps, ce latex aurait pu sécher rapidement.

En tout cas cela me semble plausible…

Bernard