Telogalla olivieri Lichenicolous fungus. Photographs on Xanthoria parietina Only parasitic on Xanthoria parietina and X. calcicola. Yellow galls are formed on the host thallus, initially slightly resembling a three-cornered hat but as the galls develop they become domed and more irregular in shape. The immersed perithecia have pale walls but are brown or dark brown round the ostioles, visible as dark spots on the surface. Asci are 8-spored, the spores 15-20 x 4-7 µm, simple, hyaline and usually with 2(-3) guttules (but can appear septate in K). Micrographs below.

Micrographs





Telogalla olivieri
On Xanthoria parietina, Kingston Lacy, Dorset. February 2020