Gyalectaceae Gyalecta biformis Growth type crustose. BLS conservation evaluation: DD NR Sc Chemical results negative. Photobiont Trentepohlia Can be either saxicolous or terricolous and occurs on basic substratum including serpentine and alkaline shale. Thin and scurfy or immersed and inconspicuous pale grey or greyish-green thallus. Apothecia initially immersed then erumpent, the urcelate buff to orange discs with pale well-developed margins. The asci are 8-spored, the spores 5-7 septate with an occasional single longitudinal or oblique septum, 21-31(-33) x (3-)4-6 µm. Micrograph below. Similar: Gyalecta derivata is corticolous, spores 7-13 septate

Microscope photograph

Gyalecta biformis
Wool, Dorset. March 2017