Accès membres

Mot de passe perdu? S'inscrire

25-04-2025 22:48

Gustaf Fredell Gustaf Fredell

Hello,I hope everything is going well. I couple mo

18-04-2025 23:16

Robin Pétermann Robin Pétermann

Bonjour, Voici une probable Mollisia, genre que j

24-04-2025 21:35

Thorben Hülsewig

Hi there,last week i could found this asco on an S

25-04-2025 17:24

Stefan Blaser

Hi everybody, This collection was collected by J

25-04-2025 09:33

Josep Torres Josep Torres

Ascomata shaped like deformed black grains, measur

24-04-2025 21:53

Lothar Krieglsteiner Lothar Krieglsteiner

... 15.7.24 in the Alps. There were many asci with

23-04-2025 20:16

Miguel Ãngel Ribes Miguel Ángel Ribes

Good afternoon Looking for Octospores / Lamprospo

24-04-2025 15:03

Henri Koskinen

Hello, I collected this Lasiobolus 22.04. near Hel

23-04-2025 19:58

Francois Guay Francois Guay

I found this interesting Orbilia sp. one year ago

22-04-2025 10:37

François Bartholomeeusen

Also found on April 18, 2025 on an old seed-pod of

« < 1 2 3 4 5 > »
Possible Hymenoscyphus fructigenus
B Shelbourne, 27-08-2024 19:03
B ShelbourneI found some Hymenoscyphus-like apothecia on cupules and acorns of Quercus robur, spores seem to fit with Hymenoscyphus fructigenus too.

Habitat: Found yesterday (late August) after some rain, on acorns and cupules of Quercus robur, in damp and shady areas under a dead hedge fence (stacked dead wood), generally quite a damp muddy area, in mixed deciduous woodland with lots of Quercus and Corylus, ~25m elevation, Lower Weald, England.

Apothecia: Several with 0.5-1.5 mm diameter and some larger ones observed, < 10 mm stipe length depending on evironment, initially whitish and more translucent, yellowing with age (especially noticeable on disc), singular to caespitose, superficial, cyathiform and eventually discoid, margin more whitish and often undulating when mature, appearing to display geotropic growth and growing out of holes in the acorns.

IKI: Rings bb, hymenoscyphus-type, VBs with strongly dextrinoid reaction.

Spores: Elongated lacrymoid in face view, base acute and apex hemispherical, constricted at the middle and scutuloid in profile view, many small to medium VBs and some tiny LBs, appearing aseptate and uninucleate.

Free spores measured in water: 17.3-20.6 (21) x 4.4-4.7 um, Q = (3.7) 4-4.6 (4.7), n = 14, mean 19.3 x 4.5 um, Q mean = 4.2.

Asci: Cylindrical-clavate, apex appears acute-truncate, 8-spored, poroid, simple septa (furcations not clearly observed).

Paraphyses: Narrow cylindrical, with many small VBs, especially towards apex, apparently several at least 2-septate, most branching close to the base.

Ectal ex: Looks like textura prismatica (typica?), some narrower external hyphae with VBs.

Medullary ex: Looks like textura intricata.
  • message #80072
  • message #80072
  • message #80072
  • message #80072
  • message #80072
Hans-Otto Baral, 27-08-2024 21:27
Hans-Otto Baral
Re : Possible Hymenoscyphus fructigenus
Yes of course, typical H. fructigenus. Exciple has a typical prismatica.
B Shelbourne, 28-08-2024 11:35
B Shelbourne
Re : Possible Hymenoscyphus fructigenus
Thank you for looking and confirming the structure of the ectal excipulum.

Do you recognise any subgroups or varieties?

On IF, 'var. carpini' was elevated to species level by Gminder (2016). I guess on acorns in Western Europe with typical morphology would suggest this collection is 'var. fructigenus'.

Hans-Otto Baral, 28-08-2024 12:00
Hans-Otto Baral
Re : Possible Hymenoscyphus fructigenus
This is unclarified. Once I thought that every host genus has its own species but data are so far lacking and morphology is very similar. H. carpini has smaller spores, though.
B Shelbourne, 28-08-2024 15:12
B Shelbourne
Re : Possible Hymenoscyphus fructigenus
Thank you. It seems not much has changed since your comments in the 1996 H. seminis-alni paper. Here you also reference collections on nuts of several genera and species.

I have seen similar apothecia on acorns before but not on hazelnuts. I can look more though as there are many around in the same wood and even close to where I found these acorns. It also seems interesting that they grow on the cupules as well as what seems to be the pericarp.


I can't find any discussion of an anamorph of H. fructigenus. Although I did find this interesting paper looking at mating genes in genomes of Leotiomycetes. I haven't read it properly yet, but they suggest many H. spp., including H. fructigenus, are homothallic. Presumably outcrossing between individuals on different nuts, if possible, would then be rarer anyway.


Wilson AM, Coetzee MPA, Wingfield MJ, Wingfield BD. Needles in fungal haystacks: Discovery of a putative a-factor pheromone and a unique mating strategy in the Leotiomycetes. PLoS One. 2023 Oct 12;18(10):e0292619.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10569646/