1. Biatorella simplex (Dav.) Br. & Rostr. Bot. Tidssk. 3: 241 1869.
Lichen simplex Dav. Trans. Linn. Soc. Lond. 2: 283 pl. 28. f. 2. 1794.
Thallus thin and smooth or thicker and roughened, sometimes subareolate, ash-white to green-gray and darkening, rarely disappearing; apothecia minute to middle-sized, 0.2 to 0.8 mm. in diameter, adnate, scattered or crowded, rounded or variously irregular, black but usually dark red when damp, flat or slightly convex, the thin exciple raised and persistent; hypothecium light or darker brown; hymenium pale or tinged brown; paraphyses semi-distinct to coherent-indistinct; asci cylindrico-clavate; spores oblong-ellipsoid, 3 to 5 mic. long and 1 to 1.5 mic. wide.
Collected in Butler, Adams, Montgomery, Hocking, and Ross counties. On limestone. Not previously reported from Ohio, but probably frequent where there is limestone, though inconspicuous and easily overlooked.
2. Biatorella pruinosa (J.E. Smith) Mudd Man. Brit. Lich. 191. 1861.
Lichen pruinosus J.E. Smith in Sowerby, Eng. Bot. 32: pl. 2244 1811.
Thallus light colored, usually thin and smooth, rarely disappearing; apothecia minute to middle-sized, 0.2 to 1 mm. in diameter, adnate scattered or crowded, flat or slightly convex, the disk pruinose, and the exciple persistent; hypothecium lighter or darker brown; hymenium usually pale; paraphyses coherent and becoming indistinct; asci cylindrico-clavate; spores oblong-ellipsoid, 3 to 5 mic. long and 1 to 1.5 mic. wide.
Collected in Butler and Adams counties. On limestone. Not previously reported from Ohio, but often occurring with the last in limestone areas.
Lecidea Ach. Meth. Lich. XXX. 32. pl. 2. f. 1, 2. 1803.