Lepraria vouauxii (Hue) J. R. Laundon

    Thallus crustose, diffuse, coarsely powdery, margin often slightly delimited, margin lobes thin and whitish, thallus surface granulose, granules to 0.1-0.2 mm diam., more or less covered with short hyphae, grey-greenish, withe-bluish, pale grey-blue, cream. Fertile specimen unknown. C+ dirty yellow, K+ dirty yellow to orange, Pd+ yellow-orange. Rather rare in our prospection area, on more or less acid and shaded rock surfaces (schists, sandstone, ...), protected from direct rain. Less frequently in crevices of tree barks. See Lepraria rigidula more greyish and Pd- and Lepraria lobificans of which the thallus is lobate and covered with soft and cotonny granules, C- and usually K-.*