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Hans-Otto Baral
Hello I want to ask you if you have found this ye
Tiny yellow apothecia on Juncus trifidus in alpine habitat
Edvin Johannesen,
17-08-2020 14:56

Hi!
This tiny (1-1.5 mm diam.) inoperculate discomycete was growing on old culms of Juncus trifidus ("probably", according to the collector who is botanically inclined) 1230 m a.s.l., which is alpine zone above the timberline in Central Norway. The habitat is described as bog/mire.
Spores are initially non-septate, but eventually develop one septum. They measure (16-)17-18(-20) x 5-6 microns and contain several guttules of varying size (live spores in water). Paraphyses are guttulate and contain yellow pigment. The apothecia are soft and do not appear to be gelatinized. I have not tested IKI reaction, doubting that it would be of major significance.
I was (mis?)lead in the direction of Calycina scolochloae, but I think that is a wrong track.
Any suggestion?
Thanks!
Edvin
Hans-Otto Baral,
17-08-2020 16:00
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
This actually requires the iodine reaction (Lugol). Shape of the ring in a turgorless ascus is necessary to see, also the colour. Croziers present?
Edvin Johannesen,
17-08-2020 16:11
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
Thanks, Zotto. I guess a turgorless ascus is one that has discharged the spores? I will try also to show the ascus basis. KOH, washing and then Lugol (or Baral's - I have both)?
Edvin Johannesen,
18-08-2020 12:47
Edvin Johannesen,
18-08-2020 12:50
Edvin Johannesen,
18-08-2020 12:52
Hans-Otto Baral,
18-08-2020 22:04
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
So it is clearly with croziers, and the asci are clearly inamyloid in my estimation. I have no clear idea, the only being Phaeohelotium monticola on an unusual substrate, with unusually long apothecial stipes.
Edvin Johannesen,
19-08-2020 10:50
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
Thanks, Zotto. I suspect I might have the same as Maren Kamke found back in 2015: >
Although the spores are slightly larger in our collection. Not sure in what medium Karen measured, though.
Hans-Otto Baral,
19-08-2020 11:01
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
Indeed! Maren surely also used water. Your spores actually are a bit too large for the species.
Edvin Johannesen,
19-08-2020 11:15
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
Thanks!
Edvin Johannesen,
20-08-2020 12:56
Re : Tiny yellow apothecia on Juncus trifidus in alpine habitat
I have now re-measured the spores and updated the numbers in the original post. They measure mostly 17-18 x 5-6 microns in water. Rarely shorter (16), and never narrower. A few spores 19-20 long. Still slightly larger than Maren Kamkes collection, but I feel more comfortable now, that they are the same.















