Accès membres

Mot de passe perdu? S'inscrire

20-04-2026 22:00

Malcolm  Greaves Malcolm Greaves

These pale yellow, hairy ascos were growing on cul

19-04-2026 21:23

Steve Clements

Bonjour, I found this anamorphic fungus on old pl

19-04-2026 20:46

Steve Clements

1 mm diameter approx spherical conidiophores on pl

12-04-2026 17:56

Hardware Tony Hardware Tony

Found on dead stems in February earlier this year

17-04-2026 19:16

Enrique Rubio Enrique Rubio

Hi to everybodyI would appreciate any assistance r

14-04-2026 05:32

Ethan Crenson

Hi all, A few weeks back a friend pointed out som

17-04-2026 15:14

Bruno Coué Bruno Coué

Bonjour.Récoltes du 16/04/2026, sur feuilles mort

12-04-2026 15:52

Gernot Friebes

Hi,I'm looking for help with this anamorph collect

14-04-2026 21:52

Gernot Friebes

Hi,found on dead leaves of Carex elata. Conidia: 4

16-04-2026 22:09

Buckwheat Pete

Hello, I'd like to ask about this older specimen:

« < 1 2 3 4 5 > »
Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020
Thomas Læssøe, 03-02-2020 20:28
https://svampe.databasen.org/observations/10080840

KOH gave a striking pink reaction at upper leves of the hymenium

cheers

Thomas
ps on some apothecia this fungus co-occured with Pyrenochaete xanthoriae
Alain GARDIENNET, 03-02-2020 21:19
Alain GARDIENNET
Re : Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020

Hi Thomas,


It fits well with Arthonia parietinaria. Epihymenium id K+ for this species, but K- for A. molendoi.


Thus, we know (since 2016  , Fleischhacker et al.), that A. parietinaria occurs on X. parietina when A. molendoi occurs more on X. elegans.


Alain

Martin Bemmann, 03-02-2020 21:34
Martin Bemmann
Re : Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020
Hi Alain, A. parietinaria was my first guess as well. But I withdrew because of the "chestnut-brown" KOH reaction stated by Fleischhacker etal:


The pink reaction observed by Thomas would fit more to A. destruens, described as "purplish violet".

However, I have no own observations.

Regards

Martin
Thomas Læssøe, 03-02-2020 21:55
Re : Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020
yes, both described colour reactions a bit off from my clear pink....
Alain GARDIENNET, 03-02-2020 21:59
Alain GARDIENNET
Re : Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020

Hi Martin,


Yes I noted this strange colour. But A. destruens is not given on X. parietina. Thus ascospores are bigger.


It would be good to check the reaction with next collections of Arthonia parietinaria. If I find time, I will check with mines.


Thomas, please keep it in herbarium under Arthonia sp. cf A. parietinaria.


Alain

Thomas Læssøe, 03-02-2020 23:19
Re : Parasite on Xanthoria parietina apothecia (arthonioid?) - Denmark Feb. 2020
will do and thanks :-)