Distribution: C - Sar (Giralt & Matzer 1994, Rambold & al. 1994).
Description: Thallus crustose, episubstratic, continuous, smooth, brownish to ochre-coloured. Apothecia lecideine, adnate to sessile, up to 1 mm across, with a concave to slightly convex, black disc, and a thick, persistent proper margin. Proper exciple 40-50(-70) μm wide laterally, aethalea-type, the inner hyphae hyaline, prosoplectenchymatous, the outer hyphae parallel and usually strongly brown-pigmented, with crystals visible under polarized light, which react K+ yellow; epithecium brown; hymenium colourless, 60-80 μm high, not inspersed with oil droplets; paraphyses capitate, the apical cells up to 6 µm wide, with a brown cap; hypothecium pale to dark reddish brown. Asci 8-spored, clavate, Bacidia-type. Ascospores 1-septate, brown with paler spore-ends, ellipsoid, (11-)12-16 x (5-)6-8 μm, Dirinaria-type, the lumina angular when young, becoming rounded when mature (Pachysporaria-type), the wall smooth to microrugulate, the torus not or poorly developed, with ontogeny of type B (apical inner wall-thickenings produced before septum formation). Pycnidia black. Conidia bacilliform, 5-6 x c. 1 μm. Spot tests: thallus K-, C-, KC-, P-; proper exciple K+ yellow. Chemistry; proper exciple with secalonic acid A (major), and an unknown secalonic acid (trace).
Note: a Mediterranean-Atlantic species, restricted to coastal localities with frequent humid, salt-loaden winds, e.g. on Juniperus on sand dunes. It is included as “Critically Endangered” in the Italian red list of epiphytic lichens (Nascimbene & al. 2013c).
Growth form: Crustose
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)