Basidiomycota. Corticiaceae Laetisaria lichenicola # Lichenicolous fungus. Photographs on Physcia tenella. Only recognised in Britain and Ireland since 2015 but widespread on Physcia species on nutrient-rich twigs. Usually develops in the upper thallus, turning it a glossy light to mid pink and appearing slightly frosted when the two-pronged basidia are produced. Subsequently host tissue degrades into a thin film. Micrographs below. Similar: Laetisaria macrospora, light pinkish basidiomata on (usually) lower surface of Physcia adscendens and P. stellaris. Basidia have four sterigmata and larger basidiospores, 23-34 × 11-18 µm. Illosporiopsis christiansenii has bright pink blobs of coiled conidia. Marchandiomyces corallinus is also pink but produces small bulbils.

Micrographs showing basidiospores



Laetisaria lichenicola
Parkstone, Kingston Lacey and Hampreston, Dorset. January 2013, December 2015, August 2023, October 2025