Teloschistaceae Xanthoria polycarpa (Polycauliona polycarpa) Growth type foliose. Chemical results: K+ crimson / purple. Found on nutrient-rich twigs, dead trees, fences and rocks affected by agricultural nitrogen. Becoming more frequent in urban areas as air pollution is reduced. Small rosettes of orange-yellowish lobes with abundant apothecia, often completely covering the thallus. The orange-brown discs become contorted, margin sometimes excluded. Asci are 8-spored, the spores colourless, polarilocular, 11-15 x 6-8 µm. Microscope photographs below. Sometimes host to the lichenicolous fungus Lichenoconium xanthoriae Photograph below with Xanthoria candelaria and X. parientina

Microscope photographs



Xanthoria polycarpa
March and October 2012, April 2013