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11-03-2026 17:36

Michel Hairaud Michel Hairaud

Bonjour, Je cherche des indices  pour cette réc

09-02-2026 22:01

ruiz Jose

Hola, me paso esta colección en madera de pino, t

11-03-2026 16:48

Bruno Coué Bruno Coué

Bonjour, je serais heureux d'avoir votre avis sur

11-03-2026 14:14

Gernot Friebes

Hi,I would like to share a collection of Scopinell

15-09-2020 17:27

Andgelo Mombert Andgelo Mombert

Bonjour, Sur branche morte décortiquée de Berbe

10-03-2026 18:08

Marc Detollenaere Marc Detollenaere

Dear Forum,On stems of Arctium, I found some downy

05-03-2026 10:07

Hulda Caroline Holte

Hello, I found and collected this species growing

07-03-2026 13:06

éric ROMERO éric ROMERO

Bonjour tous, Sur cône d'épicea fortement imbu,

23-12-2025 08:27

Josep Torres Josep Torres

Hello.Small, yellowish ascomata, with very short a

28-02-2026 11:05

Yanick BOULANGER

Bonjour à tousLe 24/02/2026 à Montmacq, devant m

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Byssonectria (?) Pyronemataceae from Eastern US
Ethan Crenson, 23-04-2024 21:49
Hello all,

A friend recently found this orange asco on bare earth in a New York City park. The apothecia are orange, turbanate, sessile growing without an apparent mycelial mat on a muddy tire rut.  The largest is 1.5 mm in diameter. They sometimes have a faint white marginal zone.

The apothecia are unfortunately immature. I am unable to find many ejected spores. The spores in ascus are broadly ellipsoid, smooth and small.  The few I was able to measure out of the asci were approximately 9-10 x 5-6µm.

The few asci present are IKI-.  Paraphyses are enlarged at the tips and contain orange pigments which stain green in IKI.

In the field I thought this might be Ramsbottomia, but the microscopy shows that it is obviously not. My next thought was Byssonectria, but the Pfister paper Synopsis of the North American Species of Byssonectria contains nothing with spores this shape and size. Byssonectria deformis, in Zotto's folder, has broadly ellipsoid spores, but much larger and it also appears to be restricted to Europe, from what I can tell.



Can anyone help with this asco?



Thank you in advance,

Ethan
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Uwe Lindemann, 23-04-2024 22:23
Uwe Lindemann
Re : Byssonectria (?) Pyronemataceae from Eastern US
Hello Ethan,

yes, I would agree that it is a species of the genus Byssonectria. The macroscopic appearance is very typical. As for the ascospores, they look immature to me. Perhaps you should wait a few more days and then examine the ascomata again?

Best, Uwe


Ethan Crenson, 23-04-2024 22:26
Re : Byssonectria (?) Pyronemataceae from Eastern US
Thank you for your comments, Uwe.  Is it possible that over the course of a few days the spores will become more fusiform in shape and grow to the size of typical North American species?  They seem so different.
Uwe Lindemann, 23-04-2024 22:34
Uwe Lindemann
Re : Byssonectria (?) Pyronemataceae from Eastern US
No, I don't think they will become fusiform.

Best, Uwe