Bryum subapiculatum Hampe, Vidensk. Meddel. Dansk Naturhist. Foren. Kjbenhavn ser. 3, 3: 51. 1872.
Protologue: Brazil. Glaziou, sub Nr. 5148.
Bryum microerythrocarpum C. Müll. & Kindb. in Macoun, Cat. Canad. Pl., Musci 6: 124. 1892. Protologue: Canada. In wet gravel, shore of Shawnigan Lake, Vancouver Island, July 1st, 1887, Macoun (MO).
Plants small to medium-sized, dull green or yellowish green, often tinged red, in loose tufts, 4–10 mm high; rhizoids moderately developed at base, papillose, with red to reddish brown, oblong to spherical, smooth gemmae, to 190 μm long. Leaves 1–2 mm long, erect when dry, erect to erect‑spreading when wet, lanceolate to oblong‑lanceolate; apices acuminate; margins plane, sometimes reflexed below, weakly bordered by several rows of somewhat narrower, long‑rectangular cells, serrulate above; costae strong, red, variously excurrent; upper cells elongate‑hexagonal, firm‑walled, 40–80 μm long, basal cells rectangular, firm‑walled, 20–80 μm long, quadrate at the lower margins. Dioicous. Setae to 15–40 mm long, reddish brown. Capsules 2–4 mm long, red, oval‑cylindrical, symmetric, pendent, neck short, narrowed and tapering to the seta; opercula 0.5 mm long, conic apiculate; exostome teeth yellow‑brown, densely papillose, endostome hyaline, lightly papillose, basal membrane to ½ of exostome teeth length, segments well-developed, narrowly perforate, cilia 2‑5, appendiculate. Spores 10 μm, nearly smooth. Calyptra not seen.