While working on an oak leaf I noticed that besides the FB of Incrucipulum ciliare there were three other FB.
Description:
FBØ 0.2-0.4 mm; tiny, white, short-stalked fruiting body (cushion-shaped hymenium) on fallen, brown oak leaf; FB turns yellow-green with KOH 3%,; discoloration of pressure points: reddish-brown;
Stem base brown in places
Ectal excipulum of thick-walled, narrow, parallel cells terminating in free tips in Margo area (many with reddish-brown contents)
Asci clavate, 8-spored, IKI blue, croziers +; - 85.7x8.5 - 81.0x8.0 - 73.9x7.4;
Paraphyses cylindrical, apically slightly clubbed, multiply septate, apical cell with strongly refractive grayish yellow VB; underlying cells also VB's, but only gray and with numerous large gas bubbles; Ø apically 3.3-3.6, below around 2 µm;
Spores ciboroid with some small LB's (oriented at poles, spore center free) OCI = 2-3
11.7-15.0 x 3.1-3.8 µm; MW(17): 14.0 x 3.5 µm; Q = 4.0

Despite intensive search, I do not come to any conclusive result.
Can anyone tell me something about the genus or does anyone know the species?

Many thanks and greetings

Stip Helleman, 29-10-2022 10:27

Re : UMO on oak leaf

Hello Harald,

Your collection reminds me of Calycellina leucella although your spores seems to be a little too wide.

This sporeshape and excipulum fits quite well.

Cheers

Stip

Harald Homa, 29-10-2022 16:13

Re : UMO on oak leaf

Hello Stip,

thanks for the tip! What still puzzles me is the substrate "oak leaf", only I have no idea how substrate specific the species is.
Also do you have any info where I can find a key or monographs on Calycellina?

Many greetings

Harald

Hans-Otto Baral, 29-10-2022 20:24

Re : UMO on oak leaf

A monograph does not exist, only for those having shorter or longer marginal bristles you can use Huhtinen's  1990 monograph (as Phialina).

C. leucella is a good idea. The brown exudate reminds me of Micropeziza, but that genus is surely closely related to Calycellina.

Stip, I have photos of yours (SBRH 1040. on Betula) with exactly the same exudate, with spores13.5-16x3-3.5.

C. leucella may well occur on Quercus, though Alnus and Betula are the usual hosts. My first record in 1975 was on Quercus.

Zotto

Harald Homa, 30-10-2022 08:15

Re : UMO on oak leaf

Hello Zotto, hello Stip,

thank you very much for the information about the species and the environment.

Many greetings

Harald