25-10-2024 22:17
Daniel GhyselinckHi everybody,Found in mountain area at about 1000m
25-10-2024 02:15
B Shelbourne• Very few macro characters and I initially thou
25-10-2024 00:26
Viktorie HalasuHello, would anyone have Häffner's article "Reze
21-10-2024 12:06
Rajamaki MarttiHi!With many other valuable species was one Geoglo
23-10-2024 16:48
Thomas Læssøehttps://svampe.databasen.org/observations/10463166
23-10-2024 17:27
Enrique RubioHi againThese tiny apothecia (100-200 µm) were gr
I found this tiny pale yellow Hymenoscyphus on twigs, leaf petioles and leaves of what may have been fraxinus in a wetland area in New York City in the Bronx. The forest was composed of ash, maple, oak and sweet gum.
The apothecia are about 1.5mm tall with a yellow hymenium. The stipe is lighter in younger specmens, but becomes brown in older specimens.
Spores are hyaline, multi-guttulate usually with 2-4 larger guttules and several smaller ones, some curved, many with one blunt end and one acute end. Dimensions:
14.2-21.6 x 3.6-6.0µm
Me: 18.6 x 4.8µm
Q: 2.4-5.3
Qe: 4.0
N=15
Asci, clavate, IKI+, with croziers. Dimensions:
91-112 x 8-12µm
Paraphyses with tiny guttules, cylindrical, about 3µm wide.
Ectal excipulum textura porrecta. Some brown pigmentation in the Ectal.
It is not certain that the substrate is Fraxineus. As far as I know Ash dieback caused by H. fraxineus is not reported from North America. (Unfortunately, I get a overwhelmed with Google results leading me in that direction if I include the possible substrate in my searches).
Any help would be appreciated.
Thanks!
Ethan
Looking at the spores, I wonder whether there are very short (1-2 µm long maxi) cilia at their ends or not ?
Amitiés Michel
I am not sure KOH would help with the observation of cilia . I join your plate with the suspected spore ends with short ones, but not sure. I also join a picture with H. scutula spores with short cilia to compare. But H. scutula has no croziers and it grows on plant stems rather than twigs.
Michel
Amitiés. Michel
Thank you all again for your help.
can you please make a section of the petiole (or rachis), in water? Some other hosts with long petiole (eg. Acer, Q. rubra) can be excluded by its anatomy.
Viktorie