Wednesday, 19 May 2010

The Wall at Rushend (2)

Here are some more of the lichens observed growing on the wall at Rushend in North Tynedale. Identification of some has proven very difficult, not least from photographs which is probably the least reliable method. I have referred to my recently acquired Lichens: An illustrated guide to British and Irish species by Frank Dobson and have also found Alan Silverdale's website very useful.

I begin with my favourite in this batch, Orthioparma subfestiva, looking rather ordinary in this general view of a young example, 7cm in diameter ...


The guide says: "There is only one British species of Orthioparma which means snake-like shield from the serpentine undulations of the margins of the apothecia, which have blood-red to dried blood coloured discs up to 4mm wide. There are two forms, ventosa (yellow-grey thallus containing usnic acid) and subfestiva (grey thallus without usnic acid). It is common in upland areas where both chemical forms may occur together." Here it is in close-up, looking anything but ordinary ...

Others whose identification I am confident about are ...


Rhizocarpan geographicum - a general view


Rhizocarpan geographicum - a close-up view


Rhizocarpon oederi


Ochrolechia parella
And finally ...


Xanthoria parietina with an unidentified Lecanorine-type above right

As ever, if anyone out there has a better idea of their identification, please do let me know.

3 comments:

Midmarsh John said...

What an amazing variety of growths on one wall Emma. Lovely clear photos.

The Early Birder said...

Excellent and informative post Emma supported by fabulous images. Not to self...must pay these growths more attention in future.

Tarset Shepherd said...

Excellent blogs Emma, it's good to see folks opening their eyes and seeing what is under their noses. A greater treat to see someone who can capture them so well on camera. Thankyou for the educational twist but I still wont be able to remember their names!