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Cushion disc on Pinus contorta
Chris Johnson,
09-02-2015 17:36
Gregarious colony on the bark of a dead twig, mostly 0.5 mm across. When moist grey to bluey-purple, almost black when dry.
No obvious amyloid reaction but not easy to see. The hymenium was heavily agglutinated and difficult to separate.
Spores 3-septate, guttulate, 17.0-24.2 x 4.3-5.7 µm, mostly tapered.
Not getting anywhere with this and would welcome pointers.
Regards, Chris
Hans-Otto Baral,
09-02-2015 17:46
Re : Cushion disc on Pinus contorta
Did you use Lugol or Melzer? It looks like a lichen, in my mind.
Javier Etayo,
09-02-2015 17:51
Re : Cushion disc on Pinus contorta
I would say it is a lichen of the genus Micarea, but hymenium reaction with I and KI should be positive.
Best wishes. Javier
Best wishes. Javier
Simon Kennedy,
09-02-2015 18:00
Re : Cushion disc on Pinus contorta
Arthonia?
Chris Johnson,
09-02-2015 18:55
Re : Cushion disc on Pinus contorta
Thanks for those quick replies. A lichen didn't occur to me. I used Melzer's but with that colour hymenium, it would be easy to overlook a reaction.
I will check out your suggestions.
Regards, Chris
I will check out your suggestions.
Regards, Chris
Hans-Otto Baral,
09-02-2015 19:39
Re : Cushion disc on Pinus contorta
When you pretreat with KOH and then add MLZ you will not overlook the reaction if it is really a Micarea or Arthonia. With Lugol you could spare the pretreatment.
Hans-Otto Baral,
09-02-2015 19:39
Re : Cushion disc on Pinus contorta
When you pretreat with KOH and then add MLZ you will not overlook the reaction if it is really a Micarea or Arthonia. With Lugol you could spare the pretreatment.
Chris Johnson,
09-02-2015 23:05
Re : Cushion disc on Pinus contorta
Ok Zotto, I will experiment with Lugol tomorrow. Micarea peliocarpa could be close.
Thanks, Chris
Thanks, Chris
Jenny Seawright,
09-02-2015 23:26
Re : Cushion disc on Pinus contorta
Hi Chris - were there any algal cells present in your sections? If its M. peliocarpa the thallus and apothecia are C+ red
Chris Johnson,
10-02-2015 11:35
Re : Cushion disc on Pinus contorta
Hi Jenny
I'm glad I persuaded you to join this forum! - although getting back into lichens is an accident at this stage.
There were a few algal cells, image attached. C was negative, so too were K and UV.
Zotto - Lugol was positive but it took quite a while.
Chris
I'm glad I persuaded you to join this forum! - although getting back into lichens is an accident at this stage.
There were a few algal cells, image attached. C was negative, so too were K and UV.
Zotto - Lugol was positive but it took quite a while.
Chris
Hans-Otto Baral,
10-02-2015 12:08
Re : Cushion disc on Pinus contorta
Yes, Chris, this is clear now. But the Lugol reaction is very fast, only it may take a while until it reaches the fungus. Melzer is even slower, and it is true that the IKI in Melzer diffuses faster than the chloral hydrate, and then you see for some seconds the red reaction which is supressed by the chloral hydrate.
If you pretreat with KOH then the whole ascus wall turns blue, not only the tholus at the apex.
See about this on my homepage:
http://www.invivoveritas.de/articles/iodine-reaction/
If you pretreat with KOH then the whole ascus wall turns blue, not only the tholus at the apex.
See about this on my homepage:
http://www.invivoveritas.de/articles/iodine-reaction/
Chris Johnson,
10-02-2015 14:22
Re : Cushion disc on Pinus contorta
Thanks for the link, Zotto, an informative paper which I will print off for reference.
Chris
Chris