Two Arachnopezizas - Forum ASCOFrance

21-04-2026 13:36

Wentiomyces-like on Salix

Gernot Friebes

Hi,I am out of ideas for this one. I collected Sal

21-04-2026 13:19

Lophodermium on Typha

Gernot Friebes

Hi,this Lophodermium on Typha has ascospores measu

21-04-2026 13:05

Hyphomycete on Typha

Gernot Friebes

Hi,this hyphomycete feels familiar but I was not a

20-04-2026 22:00

Trichobolus dextrinoideosetosus?

Malcolm Greaves

These pale yellow, hairy ascos were growing on cul

19-04-2026 21:23

Hairy anamorph on plywood with beaked curved conidia

Steve Clements

Bonjour, I found this anamorphic fungus on old pl

19-04-2026 20:46

Anamorphic fungus on plywood

Steve Clements

1 mm diameter approx spherical conidiophores on pl

12-04-2026 17:56

Seeking genus for 1 – 3 septate spored asco. on herb Nepteta cataria (Mint).

Hardware Tony

Found on dead stems in February earlier this year

17-04-2026 19:16

Small dark synnemata on rotten hardwood

Enrique Rubio

Hi to everybodyI would appreciate any assistance r

14-04-2026 05:32

Pyrenomycete with yellow subiculum on Aralia

Ethan Crenson

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

17-04-2026 15:14

sur feuilles de Luzula

Bruno Coué

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

Two Arachnopezizas

Gernot Friebes, 03-03-2014 19:08

Hi,

these two Arachnopezizas grew closely together on a soaked, strongly decayed stump. One species has whitish, very small apothecia. The other species is much more distinct, having bigger, bright orange apothecia.

The smaller one (photos of this collection are attached to this post) has 0- to 1-septate ascospores measuring 11-16.5 x 3.5-4 µm without appendages but I could observe a hyalin sheath around one ascospore. Asci have croziers, they are IKI bb, paraphyses are simple, without any remarkable content. The hairs are smooth and tapering towards the apex.

I haven't been able to find a matching species but that may also be due to the fact that I do not possess Korf's monograph: Korf, R.P. 1951 A monograph of the Arachnopezizae. – Lloydia 14: 129-180, so if anyone has a digital version I'd very much appreciate it!

PS: I should add that the macro photos are not mine.

scale = 10 µm

Gernot Friebes, 03-03-2014 19:14

Re : Two Arachnopezizas

Here's the second species. I think it may be A. trabinelloides since it fits very well the various images and descriptions I've seen of this species. However I'm not entirely sure yet how to differentiate between A. trabinelloides and A. cornuta so any advice is welcome. Ascospores measure 13.5-18(19) x 3.2-3.8 µm, they usually have a thin middle septum but can become 3-septate when overmature. Again no appendages observed. Paraphyes are somewhat irregular and filled with tiny yellow droplets. Asci are IKI bb. Hairs show an irregular outline and are incrusted by a yellowish substance. Upon adding IKI the hymenium shows a distinctive blue-green colour reaction.

Best wishes, Gernot

scale = 10 µm