On dead wood of Cytisus scoparius I found a group of tiny apothecia. Does anyone recognizes this species or is familiar with the group in which this species should be found?

Apothecia young barrel-shaped, dark brown and with a white flaky edge around the opening, older cup-shaped, up to 0.5 mm diam., dark brown with still the white edge present, sessile, base broadly attached to the substrate, base blackish brown, hymenium grey when young, older yellowish grey.
Spores 12,5-14,3 x 4,4-5,2 (10 spores meassured),
Asci 87-107x8,-9,5 ?m. J-, with clamps,
Paraphyses thread-like, septated, sometimes splitting, upto 2 ?m diam.
Excipulum composed of (only?) brown, globose thick-walled cells, towards de margin transitioning into hyphae, but I don't know whether this means the apothecia have marginal hairs,
The white flakes consist of microscopically small grains which release immediately in water.

Enrique Rubio, 14-11-2025 19:47

Re : Small species on Cytisus scoparius

Few years ago, we found the same fungus also on Cytisus scoparius, and it was sequenced. GenBank: PV477790.1

Hans-Otto Baral, 14-11-2025 20:37

Re : Small species on Cytisus scoparius

Yes, it is my folder "sanguineoatra-like Cytisus" in Skyttea. 

I wonder if KOH dissolves something from the red-brown excipulum.

JP Priou collected it on Cytisus in Bretagne and Alsac (JPP 2024120, JPP 28065), and Guy in Luxembourg on Cytisus (PP058118 Cordieritidaceae sp. G.M. 2023-07-18.1).

ITS sequences of Enrique, Guy and JP are 100% the same.

I was unaware of your sequence, Enrique, and do not have your pics. Are they online? Regrettably I have no pics from Guy.

Marian Jagers, 15-11-2025 16:40

Re : Small species on Cytisus scoparius

Adam, thanks for helping me. The collection is dried. If you still want it, I can send it to you.

Enrique and Zotto, Thanks also for your reply. It's a known species  (good to know), but apparently not officially described yet. 

Zotto, indeed, when I checked whether the granules would dissolve in KOH, to my surprise, most of the tissue dissolved. I found this rather strange that I was reluctant to mention it (and also to avoid wasting apothecia). I thought I'd wait and see what suggestions would come.  

Hans-Otto Baral, 15-11-2025 18:25

Re : Small species on Cytisus scoparius

What did you see, Marian, a red-brown stain in the medium? I would expect this since the closely related "Patinella" sanguineoatra reacts like this, the so-called ionomidotic reaction.

Enrique Rubio, 15-11-2025 20:30

Re : Small species on Cytisus scoparius

Hi.
My photos aren't ready yet. I'll send them to you tomorrow and I'll also share them here.

Marian Jagers, 15-11-2025 20:54

Re : Small species on Cytisus scoparius

Zotto, the excipulum discolored toward yellow-brown and continued to dissolve, much like the pileipellis of Xerocomus species (Boletaceae) dissolves in KOH. Only a small portion of the excipulum remained visible. I'd never seen such a reaction in ascomycetes before, hence the doubt.

I've now soaked some apothecia and repeated the test. The excipulum discolored slightly (not as strongly as yesterday), and at the beginning only a very fleeting light brown discoloration was visible. Not spectacular or intense.
Does it make any difference to the reaction whether fresh or dried material is used?