Lobaria amplissima (Scop.) Forss. phycotype amplissima
Ricasolia amplissima (Scop.) De Not.
Thallus foliose, to 30-80 cm across, most often rosette-shaped, composed of long lobes, appressed on the substratum and with more or less carboard firmness, incised, apices round, upturned or erect, lobes sometimes loosely arranged, leaving windows on the substratum below, notably towards the margin. Upper surface smooth, except towards the center where it may be wrinkled, very pale grey when dry, pale grey-greenish when moist, pycnidia on top of small warts, up to 1 mm tall, lower surface very pale brown. Old and very well developed thalli are sometimes covered with coralloid-like small heaps (cephalodia) that harbour cyanobacteria (Nostoc), and in that case, the corresponding specimen are sometimes called Dendriscocaulon umhausense (Auersw.) Degel. Apothecia rare, minute volcano-shaped at first, then sessile, 0.5-8 mm diam., disc brown-red, brown-orange, exciple distinct, pale beige to grey-orange. Ascospores narrowly ellipsoid, apices gently pointed, 1-3-septate, 40-60 x 6-7 µm. Photobiont: green algae in the thallus and Nostoc in cephalodia. Medulla: C-, K+ pale yellow, KC- or KC+ dark pink, Pd-. Rare, on bark of trunks and main branches of deciduous trees, often together with Lobaria pulmonaria and Lobaria virens. This species is under severe decline and the rare specimen amenable to observation currently are rather small and poor in apothecia.*