Bryum cellulare Hook.

Plants small, caespitose, pale green or reddish green above, reddish, yellowish or red-brown to brown below, slightly glossy; saxicolous and terricolous. Stems 3-20 mm tall, simple or branching by subperichaetial innovations, red to brown, tomentose below; rhizoids reddish brown, papillose, tubers 80-220 µm, reddish brown. Leaves equidistant, about equal in size, erect when dry, erect to erect-spreading when wet, concave; orbicular or ovate to oblong, (0.2-)0.4-0.8(-l,0) mm long; apex acute to rounded; margins plane, entire; border absent or rarely 1 cell wide. Costa weak, ending well below apex to percurrent or rarely mucronate, red or reddish brown; in section round, ventral surface cells generally present, dorsal cells incrassate to stereids, hydroids absent. Upper laminal cells lax, hexagonal or rhomboidal to subrectangular, (25-)32-100(-138) µm long, (10-)12-28(-35) µm wide; basal cells lax, subrectangular to rectangular or quadrate. Dioicous. Perichaetia terminal; leaves oblong to oblong-lanceolate, 1.0-1.8 mm long, inner leaves smaller, triangular. Seta 7-12 mm long, yellowish to reddish brown; capsule inclined to horizontal, clavate-cylindrical, urn 1.3 mm long, neck 0.6 mm long; exothecial cells thin-walled, irregular in shape, smaller towards mouth, incrassate at mouth; stomata phaneropore; annulus present; peristome double, exostome teeth yellow to orange, hyaline above, narrowly oblong-acuminate, 0.3 mm long, striolate below, minutely papillose above, endostome segments linear, narrowly perforated, ellowish to orange, cilia absent, basal membrane low; operculum conic, rostellate; calyptra not seen; spores 20-28 µm, Finely papillose.