Accès membres

Mot de passe perdu?

19-10-2025 14:10

Asco stipité sur Quercus

Camille Mertens

Bonjour à tous.Asco stipité 1mm de texture appar

17-10-2025 18:45

Sepultariella semi-immersa?

Riet van Oosten

Riet van Oosten

Hello, Found by Laurens van der Linde, Oct. 2025.

23-09-2025 13:31

"Bertia-like" Sordariales on Typha - Denmark

Thomas Læssøe

https://svampe.databasen.org/observations/10534623

15-10-2025 16:39

Tiny white apothecia on Populus inner bark

Edvin Johannesen

Edvin Johannesen

These tiny (0.2-0.6 mm), white, pulvinate apotheci

03-10-2025 13:44

Unknown on Populus -> Pyxidiophora species

Riet van Oosten

Riet van Oosten

Hello, Found by Laurens van der Linde on Populus

13-10-2025 19:05

Blanc sur tronc décortiqué

Louis DENY

Bonjour forumSur tronc décortiqué de feuillu x,

17-02-2013 21:11

Peter Welt

Peter Welt

Jamoni, P.G. 1998. Un nuovo discomicete coprofilo

11-10-2025 20:27

On Robinia pseudoacasia

Marcel Heyligen

Marcel Heyligen

Found on a barked branch, 14 mm in diameter, of Ro

11-10-2025 14:20

Chromelosporium

Jean-Luc Ranger

bonjour à tous, Je ne vois pas comment l'on peut

09-10-2025 22:14

Hymenoscphyus or Bryoscyphus? Yellow cup / white stipe

S. Rebecca

We just had the Bavarian Mycology Conference in Au

Stictis radiata sur Fallopia japonica

Bernard CLESSE, 10-01-2016 22:31

Bernard CLESSE

Bonsoir à tous,

Suite et bientôt fin de mes récoltes sur renouée du Japon. Ici je pense à Stictis radiata, d'abord parce que les apothécies sont nettement plus petites (max. 0,3 mm de diamètre) que chez Stictis stellata (diamètre parfois dépassant le mm) montré tout récemment sur Fallopia japonica toujours et que d'autre part, les spores sont ici larges de 2-2,5 mu.

Qu'en pensez-vous ?

Bernard

Hans-Otto Baral, 11-01-2016 09:42

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

I recommend to make images in vital state though I am quite sure that the oil content in the spores is low. Also a section showing the periphyses at the inner face of the margin would be helpful, I remember Sherwood makes a difference based on their measurements. Did you notice any iodine reaction?

Bernard CLESSE, 11-01-2016 11:00

Bernard CLESSE

Re : Stictis radiata sur Fallopia japonica

Hi Zotto,

Thanks for your message !

I will try to make a cut of apothecium but I admit that I do not know what are the periphyses. Would you possibly a drawing or a microscopic picture so that I know what I have to observe? I will try to redo pictures spores alive.
Regarding the iodine reaction, I just noticed a very slight blue color and diffuses into the ascus (especially upper half) with lugol but not a color "deep blue" suitable for this species.

Bernard

Hans-Otto Baral, 11-01-2016 11:35

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

If you pretreat with KOh you will get a distinct blue of the whole hymenium, without KOH the reaction is first blue the red-brown, and only at the top the hymenium is bluish.

What is meant with periphysoids (not periphyses, sorry) you can see here.

Sherwoods distinction is perhaps a bit weird, and her opinion about amyloidity may be wrong as she appears not to have understood the influence of KOH and Melzer's.

But I must admit I have no clear concept of thse two species.

Bernard CLESSE, 11-01-2016 20:56

Bernard CLESSE

Re : Stictis radiata sur Fallopia japonica

Hi Zotto,

Thank you for your explanations !

Here are some new pictures :

a) hymenium+KOH+lugol : well blue !
b) ascus+lugol : dextrinoid; ascus cap : 3,5 mu thick
c) spores guttulated

What do you think about that ?

Bernard

Hans-Otto Baral, 11-01-2016 22:30

Hans-Otto Baral

Re : Stictis radiata sur Fallopia japonica

Oh look, these guttulate spores are exceptional, I don't know that from radiata or stellata. But I don't know these species well or can separate them.

A red reaction inside the ascus could be due to glycogen and would then be called dextriniod, but then it should be seen also after KOH, or in Melzer without KOH. What reacts blue after KOH (I think the ascus wall surface) must be red in IKI without KOH (hemiamyloid). See my homepage:
http://invivoveritas.de/articles/iodine-reaction-in-ascomycetes-why-is-lugols-solution-superior-to-melzers-reagent/
Fig. 2 and 5.