Usnea dasypoga (Ach.) Nyl.

    Thallus tufted, pendulous, beard-like, made of a few main branches, 10-40 cm long, blackened at the base near the substratum, diameter homogenous, and of very abundant secondary branches, resembling to elongate fibrils, 0.5-2 cm long, originating at right angle, and looking like Christmas tinsels, main branches covered with isidia and papillae but without soralifer tubercules, overall colour pale grey, pale gey-greenish, pale yellow-greenish. Apothecia unknown in our prospection area. Photobiont: trebouxioid. Thallus : C-, K+ yellow > red, KC-, Pd+ orange. This species, rare in Brittany, has Northern trends, and mainly grows on coniferous and birch trees. Critical in Brittany where it probably has been overestimated due to the inappropriate practice of denominating many pendulous and densely tufted usnea with long branches under this name. Most often it may be Usnea ceratina that is very common and has a similar aspect (but C+ golden-yellow, K- and Pd-).*