Until 25th January I had never identified a lichen for myself, and my experience of the group is based on being shown 4 species at Parham Park in May 2012, including the unforgettable Caloplaca flavorubescens. So on a quick walk round my snow-covered 1km square I decided to have a go at a lichen – something that looks easy and common, to get me started. I picked a twig covered in a familiar-looking yellow lichen and stuck it in my pocket.
As I’d hoped, the yellow lichen was easily identified using online keys as Xanthoria parietina: a very common lichen.
What I hadn’t bargained for was that, under the microscope there were clearly other lichens on the twig of a much less conspicuous nature. Using this key, I made the one with black “wine gum” fruits Lecidella elaeochroma and Simon Davey agrees.
Slightly more difficult to identify was this species with “jam tart” fruits. With Simon’s help, I’ve got it to Lecanora chlarotera. I was pleased enough with three lichens on my random twig but then as a further bonus, Simon pointed out that the black dots in some of the tart fillings are caused by a parasitic (or lichenicolous) fungus by the name of Vouauxiella lichenicola. Just amazing!
There was a negative reaction to a drop of thin bleach.