Teloschistaceae Polycauliona polycarpa (Xanthoria 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



Polycauliona polycarpa (Xanthoria polycarpa)
March and October 2012, April 2013