Dear Renée,

My first impression would be H. fibrosa (=H. chinensis, H. villosa etc.)
Morphologically most similar species is H. cupuliformis when all microscopical characters are taken into account. My collections (17 tested) of H. fibrosa has spores *17-21×10,5-12,5(13) micr. vs. H. cupuliformis (11 tested) *18-22×12,5-14(15) micr. Superficially looking, H. ephippium is quite confusing if pileal vertical median section is not mounted in CB (cotton blue). Contrary to preceeding +/- *regularly cupulate two species, H. ephippium with normally *lightly saddle-shaped pileus in full maturity, does not have upper medullar horizontal hyphae but instead it has scattered sphaerocysts. In distinction of first two, ectoexcipular wall thickness and colour are also very helpful. H. cupuliformis has cinnamomeous golden walls *0,6-1,7 micr. vs. greyish-yellow walls *0,4-0,7 micrs thick in H. fibrosa. Additionally, H. cupuliformis has much shorter abruptly *whitish stipe and different ecology. In SE Europe, H. cupuliformis is confined to Pinaceae, mostly Abies, while H. fibrosa is normally found under Quercus.

NOTE: Asterisk of course indicate living state of the character.

Cheers,
Neven

Je suis d'accord avec Neven :)
Par exclusion, ce n'est pas H. ephippium, ni H. cupuliformis, ni H. rivularis... Reste donc H. fibrosa !

Un article indispensable à lire sur le sujet :
Carbone M. 2011. Contributo alla conoscenza di Helvella rivularis, una specie critica e poco conosciuta della sez. Macropodes. Mycologia Montenegrina, 13 : 7-39.

Toutes ces espèces sont illustrées et comparées.

Un grand merci Neven et Nicolas. Nicolas, vous n'auriez pas une copie de cet article. Je n'y ai pas accès ici.

Renée

Demandez à Matteo Carbone : matteocarb@hotmail.com">matteocarb@hotmail.com

Merci Nicolas.

Bonsoir,

En effet, l'article dans Mycologia Montenegrina est intéressant, mais je trouve qu'on reste un peu sur sa faim car les critères de distinction entre H. rivularis et H. fibrosa sont vraiment très minces et sont peu argumentés.
Si la distinction se fait sur base de la couleur et de la villosité, il y a de nombreuses observations de H. villosa en région bruxelloise (où elle est assez commune) qui pourraient se rapporter à H. rivularis, comme par exemple cette récolte de 2000.
A contrôler sur les prochaines récoltes donc...

Cordialement,
Daniel

Good evening Forum!

I must say I concur with Daniel. Indeed, we had several grey cupulate Helvella collections with longer semipigmented stipe here settled in innundation zone of some Croatian and Slovenian creeks and small rivers that someone might have called H. rivularis, but I never found any substantial differencies from "normal" H. fibrosa (in terms of vital macro- & micromorphological view, cyto- and hystochemistry) equally also in characters that are usually critically important in distingushing closely related and/or most similar Helvella species as much as in the others!

Therefore, I am so far not convinced in H. rivularis to be a separate species. However, it would be wise to at least analyze type material that still may be something different from the idea of what some workers consider to be H. rivularis! Molecular analysis would be also desirable as well.

Cheers,
Neven