Roccellaceae Gyrographa gyrocarpa (Opegrapha gyrocarpa) Growth type crustose Soralia K-, C+ red, KC+ red, P-, UV+ glaucous or pale yellow Found on shaded neutral or siliceous rocks, often on old dry-stone walls and on rocks in old woodland. Sometimes host to Sphinctrina turbinata Thin or finely cracked pale brown to reddish-brown thallus, sometimes with pinkish patches. Dark-brown to black prothallus. Yellowish soralia scattered over surface giving flecked appearance. Occasional scattered knot-like or gyrose apothecia, spores 3-septate 17-25 x 4-6 µm. Thallus can form extensive mosaics. Microscope photograph below. Similar: Belonia nidarosiensis. On limestone, mortar and cement. C-

Microscope photograph

Opegrapha gyrocarpa
Lychett Matravers and Colehill, Dorset. January 2014, 2017