pf339's picture

Green-yellow crustose lichen

Observed: 10th April 2013 By: pf339
S159 Neighbourhood Nature - course complete
pf339’s reputation in Fungi and Lichenspf339’s reputation in Fungi and Lichenspf339’s reputation in Fungi and Lichenspf339’s reputation in Fungi and Lichens
Green-yellow crustose lichen b
Green-yellow crustose lichen a

Areolate crustose thallus, covered in green-yellow granules, growing on brick wall buttress. Lecanorine apothecia with yellow-orange discs and granules around thalline margin. K+ crimson. Possibly Caloplaca citrina.


Caution: Do NOT use iSpot to identify fungi to eat!

Some fungi are very poisonous so a mistaken ID could have serious consequences.

Species interactions

No interactions present.


synan's picture

Recent developments

British "C. citrina" is more likely to be Caloplaca limonia or a taxon that needs more work, C. aff. austrocitrina. True C. citrina may not occur in Britain at all.
See BLS Bulletins 109 and 110 or the links below:

BLS Bulletin 109
BLS Bulletin 110

Edit: links to photos removed because they don't remain static.


gardener's picture

Or Candelariella?

synan's picture


... in the description above ;)

pf339's picture


Many thanks for help and suggestions and especially the links to more information. (Identification certainly not straightforward!)

synan's picture

It's also worth...

having a quick look at the observations Alan has identified as C. limonia:

Sadly, a detailed posting I remember him offering on a third observation has 'disappeared' from iSpot.