Grimmia laevigata (Brid.) Brid.

Plants medium-sized, in loose tufts, dark grey-green, hoary, or rarely yellow-green; saxicolous or terricolous. Stems erect, to 20 mm tall, branching below; in section central strand small, inner cortical cells in 4-5 rows, large, outer cortical cells in 2 rows, smaller, incrassate. Leaves appressed dry, spreading wet; concave, lamina bistratose above; ovate to broadly ovate, 3-4 mm long; apex broadly acute, frequently hyaline, extended into a long, spinose, hyaline awn, to 2 mm long, hyaline apical cells frequently decurrent down margins of upper leaf; margins plane, entire or serrate at apex. Costa broad below, quickly narrowing, weak above mid-leaf but extending to apex; in distal section guide cells 2, exposed ventrally, dorsal stereid or substereid band small, 2-3 cells thick, dorsal surface cells larger, incrassate. Upper laminal cells quadrate to transversely short-rectangular, somewhat longer at basal angles; lower juxtacostal cells elongate, merging with costa, rarely undifferentiated. Dioicous. Perichaetia terminal; leaves sheathing, oblong-aristate, to 4 mm long. Seta short, straight, 1.0-1.5 mm long, yellowish; capsule emergent, urn elliptical, 1.0-1.5 mm long, smooth, light brown; peristome teeth cleft above, smooth, reddish yellow; operculum short-rostrate; spores round, 12-14 µm, smooth.