Pohlia richardsii Shaw, Contr. Univ. Michigan Herb. 15: 253. 1982.
Protologue: Costa Rica. Volcán Poas, on banks of volcanic ash near edge of water, c 2,500 m, 20 Feb. 1965, Richards R 6010.
Plants slender to medium-sized, dull, green to yellowish green in loose or dense tufts. Stems 4–20 mm high, dark red, simple or irregularly forked; rhizoids reddish brown, papillose-roughened. Leaves distant or crowded above, 0.7–1.4 mm long, erect to erect-spreading, stiff, not contorted when dry, lanceolate, long decurrent; apices acute; margins plane, entire below, serrulate above; costae yellow above, reddish at base, percurrent; upper cells rhomboidal, thin- or firm-walled, 30–60 x 6 μm, basal cells longer, broader and laxer, narrowly rectangular to rhomboidal. Gemmae in upper leaf axils, spheroid to ovoid, red to orange-red. Dioicous. Perigonia terminal, gemmiform. Setae 10–25 mm long, red. Capsules horizontal to pendent, 1.5–2 mm long, ovoid and constricted at neck; exothecial cells isodiametric to short rectangular, strongly bulging mammillose, with straight walls; stomata superficial or slightly immersed; opercula conic, apiculate, 0.5 mm long; annuli separating irregularly; exostome teeth whitish to light yellow, fused at base, narrowly triangular, densely papillose, endostome whitish to pale-yellow, basal membrane to _ the exostome length, segments narrow, linear, not or scarcely keeled, papillose, cilia absent. Spores 10–20 μm, lightly papillose.