Leptogium britannicum P.M. Jorg. & P. James

    Thallus foliose, rumpled paper ball-like, to 10 cm diam., lobes very thin, transluscent, pleated and round, 3-8 mm long, grey-brown, grey-greenish when moist, grey-bluish when dry, lower surface pale grey, rhizines absent. Apothecia very rare, laminal, stalked, 0.8-1.2 mm diam., disc concave, then plane, brown-red, exciple soon excluded, pale brown. Ascospores broadly ellipsoid, sub-muriform, 3-4-septate, 20-30 x 6-7 µm. Photobiont: Nostoc. Chemical spot tests negative. Maritime trends, on soils in rock crevices  or on the ground at the base of rocks.*