ASCOMYCOTA LECANOROMYCETES > TELOSCHISTALES > Teloschistaceae

Common name:            Pin-cushion Sunburst Lichen

Synonym:                    Xanthoria polycarpa

Habitat:                         Montane (for this entry)

Substrata:                     Bark, weathered wood

Growth form:                Corticolous and lignicolous

Thallus:                  Foliose

Apothecia:                    Lecanorine

BLS identity rating:        Graded 1/5 (identification should be straightforward)

Thallus forms small rosettes, typically up to 2cm dia., occasionally a little larger, but 3cm max; lobes small and very narrow, 0.5-2mm, convex and incised at the tips to form short, finger-like lobules (just visible, bottom right in this photo); upper surface usually bright yellow or bright orange, but often greenish-grey, particularly in the shade; that said, the thallus is normally pretty much obscured by the numerous apothecia; the stalked apothecia grow to 4mm dia., and sit in tight groups, often over-spilling the thallus, the flat discs are bright yellow to dark orange with a slightly paler thalline margin, which usually becomes distorted and somewhat crenulate due to age and overcrowding.

The small specimen featured here was photographed on the side of an exposed timber decking support rail of an alpine chalet. It is widespread in the Alps where it is known as Polycauliona polycarpa and, consequently, may be a different form of the species that we list as Xanthoria polycarpa. In Austria it is considered as a mainly boreal-montane lichen found on isolated trees and sun-exposed branches and small twigs, but also on weathered wood.

I haven't seen the British species, but understand that it's widespread and common, especially near the sea, occurring on nutrient-rich trees, usually in the angle of twigs, but also found on fences and deadwood.