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Niesslia-like Perithecia on Well Rotted Alnus Trunk
Peter Thompson,
13-05-2018 12:43
I have found some tiny, spherical perithecia with short hairs growing on decorticated and well decayed wood from a trunk of Alnus glutinosa.
The hairs are thick walled, dark brown, with bulbous bases and rounded tips. They strongly resemble the rigid hairs of species of Niesslia, typically measuring 82.5 - 92.5 x 5.25 um.Â
The spores are 8- 11-septate, filled with tiny drops in all cells and typically measuring 56 - 65 x 8 - 8.5 um. Hyaline and tapering to rounded ends. there are 8 spores per ascus. The ascus tips show no reaction to lugol.
I have attached a photo of the fruit bodies and a micro photo of the hairs, asci and spores.
I wonder if anyone has an idea as to what they might be?
Thank You,
With Best Wishes,
Peter.
Gernot Friebes,
13-05-2018 12:51
Re : Niesslia-like Perithecia on Well Rotted Alnus Trunk
Hi, Peter,
the ascomata and ascospores remind me of Acanthostigma – it might be worth looking into that direction.
Best wishes,
Gernot
the ascomata and ascospores remind me of Acanthostigma – it might be worth looking into that direction.
Best wishes,
Gernot
Peter Thompson,
13-05-2018 18:36
Re : Niesslia-like Perithecia on Well Rotted Alnus Trunk
Hello Gernot,
Thank you for your reply.
Acanthostigma is an unfamiliar genus for me, so I have had a look into the options for host type and macro / micro characteristics and I now believe that my sample is A. minutum.Â
Thank you for your help.
With Best Wishes,
Peter.
Thank you for your reply.
Acanthostigma is an unfamiliar genus for me, so I have had a look into the options for host type and macro / micro characteristics and I now believe that my sample is A. minutum.Â
Thank you for your help.
With Best Wishes,
Peter.

