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When: 2016-05-07

Collection location: Serra de São Mamede, Portugal [Click for map]

Who: zaca

No specimen available

Growing on siliceous rock.


Microscopy: Asci and spores (mainly young)[in KOH];
Microscopy: Apothecial sections [in water];
Microscopy: Apothecial sections – close ups [in water];
Microscopy: Apothecial section [in water] and its (no) reaction to KOH;
Microscopy: Asci [in KOH];
Microscopy: Spores [in KOH].

Proposed Names

29% (1)
Based on microscopic features: C-, K+ pale yellow
58% (1)
Used references: British Flora
Based on microscopic features
Based on chemical features

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= Observer’s choice
= Current consensus


Add Comment
Microscopy added.
By: zaca
2016-05-13 15:49:18 CDT (-0500)

Chemistry results obtained under the microscope:
Medulla: K+ yellow and I- ; On section (hymenium, epi- and hypo-hymenium): K-.

Taking into account the similarity between this specimen and that of observation 202029, in particular, I thought that it should be R. badioatrum. I also recall the difficulties in reading the KOH reactions at the time. Thus, when I first got a generalized K- reaction on the section, I repeated it and again the same result. I thought that the KOH could be out of date, though that is not usual. Finally I repeated it again now with KOH at 20% from a brand new botle and the result was the same. Then I conclude that R. badioatrum has to be ruled out. I decided to get the KOH reaction of medulla, giving K+ deep yellow and also confirmed the I- medulla. Therefore, I think that this is Rhizocarpon jemtlandicum. This species already appeared in the discussion of the observation mentioned above and, at the time I thought that it doesn’t exist at this part of Europe, but I was wrong and it appears in the checklist of the Iberian Peninsula.