I have been puzzling over specimens of Fuscolachnum growing on dead leaves of Rubus fruticosus, and in particular the distinction between F. dumorum  and F. misellum.

Details of the specimen illustrated are as follows:

Apothecia <150 µm diameter; pale brown hymenium; short-stalked to sub-sessile; hairy outer surface.

Excipulum apparently a textura prismatica (but difficult to see clearly).

Asci 35-45 x 5-7 µm; arising from croziers; blue apices in IKI.

Spores clavate; 6-8 x 2 µm; with a few small oil bodies.

Paraphyses narrowly cylindrical; 1-1.5 µm wide; about as long as asci.

Hairs brown; granular throughout; 25-40 x 3-4 µm.

I have very little information on F. misellum, but I believe one of the key differences between this species and F. dumorum is the form of the paraphyses. For example, the keys to Hyaloscyphaceae on the Mycokey website describe the paraphyses of F. dumorum as lanceolate 2-3 µm wide, and the paraphyses of F. misellum as cylindrical  1-2 µm wide. This distinction seems to be confirmed by the images on Ascofrance. Images of the two species on Ascofrance and elsewhere also seem to suggest that in F. dumorum asci arise from simple septa, whereas in F. misellum they arise from croziers.

On this basis I believe that my specimen is F. misellum, but I would be interested to hear from anyone who has experience of this species.

Many thanks

Marcus

Michel Hairaud, 18-01-2014 15:07

Re : Fuscolachnum dumorum and F. misellum

Hi Marcus, and every one

I have no experience of F. misellum but collected F. dumorum several times which is obviously different in all points you mention (paraphyses crosiers, spores length)  . 

Rene  already gave you the link to his descrition of F. misellum. I suppose you also have Haines paper on Fuscolachnum ? If not I can help in some way. 

Amitiés
Michel

Peter Püwert, 19-01-2014 22:48

Re : Fuscolachnum dumorum and F. misellum

Hello in the round,
here some macrophotos from Fuscolachnum dumorum and misellum. The micros are no passable, but to make these new is no problem, F. dumorum is common on Rubus fruticosus- leaves.
Marcus, I have send You the paper.
Greetings Peter.

The first and second are F. dumorum, the others F. misellum.

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Michel Hairaud, 20-01-2014 08:35

Re : Fuscolachnum dumorum and F. misellum

OK Nina. 

Michel

Nicolas VAN VOOREN, 20-01-2014 12:02

Re : Fuscolachnum dumorum and F. misellum

The link on Ascomycete.org (to download the key made by René) has been repaired.

Luc Bailly, 22-01-2014 12:14

Re : Fuscolachnum dumorum and F. misellum

Bonjour à tous,
Je serais intéressé aussi par la clé des Fuscolachnum de René Dougoud.
Merci d'avance, amitiés - LUC.

Luc Bailly, 22-01-2014 13:53

Re : Fuscolachnum dumorum and F. misellum

Oh, okay, thank you!

Je devrais faire un index de tout ce que j'ai sur Ascomycete.org et l'imprimer. Je vais m'y atteler.