Distribution: N - TAA, Lomb, Piem (Isocrono & al. 2004), VA (Piervittori & Isocrono 1999).
Description: Thallus crustose, endosubstratic or thinly episubstratic, dirty white to grey, continuous to minutely granular. Apothecia frequent, sessile, slightly constricted at base, 0.2-0.5(-0.7) mm across, with a flat to mostly strongly convex, rusty-orange, orange-brown, olive-orange to blackish orange, pruinose disc, a granular, grey, thin, ephemeral thalline margin, and an orange to often olive-green to blackish, somehow shiny, thin, smooth proper margin. Exciple to 60 μm wide, greyish in outermost part, the pigmented parts K-, N+ red in section; proper exciple prosoplectenchymatous; epithecium orange, K+ violet-red; hymenium colourless, 80-90 μm high; paraphyses slender, 1-3 μm thick at base, not anastomosing, simple or furcate, submoniliform in upper part, slightly thickened above; hypothecium colourless, up to 110 μm high. Asci 8-spored, cylindrical-clavate, Teloschistes-type. Ascospores 1-celled to apparently and indistinctly 1-septate, hyaline, fusiform-elongate, sometimes narrower in the centre, (22-)24-38 x 3-5(-6) μm, the equatorial thickening (“septum”) < 2 μm. Photobiont chlorococcoid. Spot tests: thallus K-, C-, KC-, P-; apothecia K+ red. Chemistry: thallus without lichen substances; apothecial disc with emodin, fallacinal, parietin, parietinic acid, and teloschistin; apothecial margin with the Cinereorufa-green pigment.
Note: a cool-temperate to arctic-alpine, circumpolar species found on silicicolous mosses (especially Andreaea and Grimmia). The statement of Printzen (1995) that the type of Biatora livida is Fulgensia schistidii is wrong: the type material of the former species, analyzed by M. Tretiach (pers. comm.), clearly belongs to Caloplaca nivalis.
Growth form: Crustose
Substrata: soil, terricolous mosses, and plant debris