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Lichen ac (ii)

Observed: 16th January 2012 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
Lichen ac (i)
Lichen ac (ii)

Light grey crustose lichen growing on concrete paving slab. ‘Crazy paving’ lines on thallus across all of lichen rosette. Many black centred ‘jam tart’ apothecia with some centres slit shaped. Possibly Aspicilia calcarea


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.


pf339's picture

Aspicilia contorta subsp. hoffmanniana

Thank you for help in identifying this lichen especially highlighting the significance of the substrate.

gardener's picture

Identification needs confirming!

My identification needs confirming by AlanS to be 100% certain!

Substrate details are vital for the identification of many lichens as some are only found on trees, some only on rocks or walls.

Then it helps to know the tree species or whether the rock was acidic or basic (limestone etc) or if it was on concrete or mortar.

Probably the most comprehensive on-line guide with substrate details for British and Irish species is the LichenIreland website:

Another excellent resource is Alan's website:

pf339's picture


Many thanks. Much appreciated.

AlanS's picture


"My identification needs confirming by AlanS to be 100% certain!"

If only that were true!!!


P.S. hoffmanniana is in really good form on concrete wall cappings here just now - I shall try to get an improved picture for my website.

The mention of A. calcarea as a possible identity makes a good point. Initially, as A. contorta subsp. hoffmanniana began to appear and spread on urban concrete, it was indeed identified as A. calcarea. The latter grows, for example, on limestone tombstones, so urban records should not all be dismissed, but quite a lot of urban records should be!

pf339's picture

A. contorta subsp. hoffmanniana and A. calcarea

Thank you for the information especially the point that A. calcarea may be around as well but on limestone not concrete.