Acarosporaceae Myriospora smaragdula (Acarospora smaragdula) Growth type crustose Chemical results usually K+ red, C-, KC+ red, P+ yellow. Rarely K- or KC- On sheltered +/- base-rich siliceous rocks, sites rich in heavy metals and on sheltered stones below metal run-off. Variable. Thallus usually pale creamy brown but yellowish-green on copper-rich rocks. Scattered flat to convex areoles that can form continuous crust. Usually 3-7 apothecia in each areole, red-brown to blackish, margins absent or well developed. The asci are >100-spored, spores 2-5 x 1-2 µm. Microscope photograph below. Similar: A. fuscata. Brownish areoles, K-, C+ red, KC+ red. Larger spores

Microscope photograph



Myriospora smaragdula, Acarospora smaragdula
Kimmeridge and Lytchett Minster, Dorset. March 2014, December 2016