Blastenia ferruginea

Crustose epiphyte, thallus white-grey, 5cm across, black prothallus. Apothecia biatorine, abundant 0.5-2 mm diameter, disc and margin rust red.
Distribution: Worldwide.

Asci 8-spored, ascospores 2-celled, polarilocular, hyaline, 12-17 x 7-10 μm, septum 6-7 μm. 
Thallus: K-, apothecia K+ red; apothecia margin C+ purple in section.

Position in classification: Teloschistaceae, Teloschistales, Lecanoromycetidae, Lecanoromycetes, Pezizomycotina, Ascomycota, Fungi.
Locality data:
Location: Bosc de Bosoms, Guixers (Solsonès)
Ecology: On a twig of Quercus pubescens.
Altitude: 836 m
Climate: Eastern Pre-pyrenean Mediterranean (Tmm=10,0ºC,  850 mm)