Teloschistaceae Polycauliona phlogina (Caloplaca phlogina) Growth type crustose. Photograph left identified by B Edwards Chemical results: Thallus and soredia K-. Apothecia K+ red Rare and declining on nutrient-rich bark of deciduous trees, mainly found on mature Elm and Sycamore. BLS conservation evaluation: NE ?NS Thin, smooth thallus, whitish-green to greenish-yellow thallus with circular pale greenish-yellow soralia. Apothecia with yellow discs, often white-pruinose, margin often esoridiate. Asci 8-spored, spores (9-)10-13 x 4-7 µm, the septum 3-4(-6) µm wide. Microscope photographs below. The orange apothecia in left photo are Caloplaca ulcerosa

Microscope photographs



Polycauliona phlogina, Caloplaca phlogina
Upton Park and Broadstone, Dorset. January 2013, January 2024