15-10-2025 16:39
Edvin Johannesen
These tiny (0.2-0.6 mm), white, pulvinate apotheci
03-10-2025 13:44
Riet van Oosten
Hello, Found by Laurens van der Linde on Populus
13-10-2025 19:05
Louis DENYBonjour forumSur tronc décortiqué de feuillu x,
11-10-2025 20:27
Marcel Heyligen
Found on a barked branch, 14 mm in diameter, of Ro
09-10-2025 22:14
S. RebeccaWe just had the Bavarian Mycology Conference in Au
10-10-2025 00:49
Ethan CrensonHello all, This was found last weekend on a hardw
04-10-2025 02:13
Francois Guay
Hi everyone, I found this Hymenoscyphus growi
Calycellina spiraeae spores
Chris Yeates,
21-10-2021 13:26
Bonjour tous
While processing images of this delightful little fungus I noticed that some of the ascospores show a distinct hyaline "sheath". I dismissed the possibility that it was an artefact, largely because it does not show on all the spores photographed in exactly the same way. As you can see it is also evident in the spore seen "end on".
I can easily see that this might be missed by normal light microscopy but wondered whether any other members have noticed this phenomenon?
Cordialement, Chris
Hans-Otto Baral,
21-10-2021 17:13
Re : Calycellina spiraeae spores
Yes, this is a sheath, and it is also visible without DIC :-)
Perhaps the spore surface staines lilac in CRB, which is due to a gel below this sheath.
Enrique Rubio,
21-10-2021 17:37
Re : Calycellina spiraeae spores
I think that these ephemeral sheaths are very frequent in the ascopores just ejected from the ascus in many Helotiales. What happens is that unless they are very conspicuous they go unnoticed.
Chris Yeates,
21-10-2021 20:23
Re : Calycellina spiraeae spores
Thank you both for these comments.
Chris
Hans-Otto Baral,
21-10-2021 20:51
Re : Calycellina spiraeae spores
Strange is that they are no always seen in a species. Just in C. spiraeae I see them in ERD 4803 but not in ERD 5959. The mentioned lilac stain with CRB seems specific for Calycellina (and some distantly related genera), but absent, e.g. in Calycina. For C. spiraeae, however, I see I once tested CRB and it was negative. But whether this is a good Calycellina is not sure (no sequence).
Enrique Rubio,
21-10-2021 20:59
Re : Calycellina spiraeae spores
What concentration of CRB do you use to try to stain the sheaths?
Hans-Otto Baral,
21-10-2021 21:55
Re : Calycellina spiraeae spores
I cannot say. There is no high concentration necessary, The medium may look hyaline but the gel on typical Calycellina spores attracts the dye.
Enrique Rubio,
24-10-2021 09:30
Re : Calycellina spiraeae spores
Thanks, Zotto.