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29-05-2026 15:35

Fusarium sur Robinier
daniel FERRE

Bonjour à tous,Je voudrais votre aide pour cette

28-05-2026 16:15

Literature request: Caloscypha fulgens f. caesioalba
James Mitchell

Hello,Does anyone have the original publication of

28-05-2026 11:06

Stictidaceae (?) on Typha latifolia - short-spored, I+ - Denmark
Thomas Læssøe

https://svampe.databasen.org/observations/10596750

23-05-2026 11:44

Coprophilous pyrenomycete wild boar dung
Charles Grapinet Charles Grapinet

Hello, I am having trouble identifying this copro

25-05-2026 16:44

Ascomata under epidermis Carex
François Bartholomeeusen

Hi forum members,During an excursion organised by

26-05-2026 21:25

small ascomycetes on Quercus sp.
Dirk Gerstner

Hello everyone, I'm completely stumped by this li

26-05-2026 22:44

Incrucipulum capitatum ?
Ethan Crenson

Hi all, I think I have Incrucipulum capitatum her

22-05-2026 14:44

minute Saccobolus from cow-dung (moist chamber from Portugal)
Lothar Krieglsteiner Lothar Krieglsteiner

in unripe condition citrine yellow, then soon fadi

25-05-2026 16:35

Anamorphe d'Hypomyces aurantius ? sous saule cendré (Salix cinerea)
Bernard CLESSE Bernard CLESSE

Bonjour à toutes et tous,J'ai trouvé récemment,

22-05-2026 13:29

Pseudophacidium ?necans on Vaccinium myrtillus
Gernot Friebes

Hi,I am curious to hear your opinion on this mater

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Coryneum (?) acervuli on oak (?) branch
Ethan Crenson, 12-01-2026 22:02
Hello all,

I am hoping someone will have some insight into this interesting asexual fungus I found on hardwood (probably oak) in a New York City park yesterday. It appears to be erumpent, gelatinous acervuli which bristle with conidia on the surface. When cut the solid interior of the acervuli are black (when fresh) and gelatinous. As they age and hollow out they become tan.


The conidia are brown, very thick walled, multi-septate, and shaped like bowling pins. Sometimes they are curved. There are wavy striations in the flanks of the conidiospores. I am reminded of the conidiospores of Helminthosporium velutinum, but of course that does not produce acervuli like this.


I have seen some discussion/images of the genus Coryneum which seems similar. Can anyone point me in the right direction?


Thanks!
Ethan

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Mathias Hass, 13-01-2026 08:01
Mathias Hass
Re : Coryneum (?) acervuli on oak (?) branch
Hi Ethan

I agree with Coryneum (or teleomorph name Pseudovalsa). There are several species on oak. The dimensions of the conidia might be helpful.

Cheers Mathias
Ethan Crenson, 13-01-2026 21:06
Re : Coryneum (?) acervuli on oak (?) branch
Mathias, 

Thanks for the confirmation on genus.  I guess I did forget to include conidia measurements.  

The larger spores (I excluded the "stunted" looking ones) measure:

76.7-101.9 x 15.3-21.1µm

Me: 91.4 x 18.2µm

Q: 4.4-5.4

Qe: 5

N=9

I have counted from 7 to 11 distosepta in the conidia that I have illustrated here.

I found a key in J. Muthumary; B.C. Sutton. (1986). Coryneum quercinum sp.nov. on Quercus alba from India. , 86(3), 0–515. The key treats Coryneum on Quercus only, so I hope that my ID of the substrate is correct.  

I am unable to see the conidiophores (I am assuming I would need a microtome to section the gelatinous material properly).  But I feel I can exclude C. quercinum based on dimensions of the conidia.  Which leaves the next option at C. megaspermum var. megaspermum "Conidia with up to 11 distosepta, 76-100 x 12-15." The conidia in my collection are somewhat wider. Continuing in the key I get to C. neesii, but the length and number of distosepta doesn't match. 

So I'm left with perhaps C. megaspermum var. megaspermum with conidia somewhat too wide. 

Or maybe I have the wrong substrate.

Ethan
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