Lichen - resembling chipped flint nodules

[Bruce Williams]

Stony Stratford, Bucks. On sandstone (I think) block.

Help with identification appreciated as always:



Bruce

[AlanS]

Hi Bruce,

Main subject is Aspicilia contorta subsp. contorta, naturally occurring on base-rich rocks such as limestone or basalt, but also increasingly common species in urban areas on concrete, paving stones etc.

A second subspecies, hoffmanniana, is also common in urban areas now - limited information on my website but I have better pictures of both subspecies to be posted in the fullness of time. Both are 'chewing gum' lichens - looking just like discarded chewing gum when growng on pavements.

Bottom left, under your signature, you have Verrucaria viridula.

The scattered yellow discs are a Candelariella, quite possibly C. aurella, but it needs microscopic examination to separate it from dispersed forms of the related C. vitellina and it is probably over-recorded. I wouldn't give it a definite ID from a photograph.

Alan

[Bruce Williams]

Thanks for your help with the ID's Alan - and for the extra info too.

Bruce