Brachymenium systylium (C. Müll.) Jaeg., Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1873–74: 117. 1875.
Bryum systylium C. Müll., Syn. Musc. Frond. 1: 320. 1848. Protologue: Mexico. Prope Xalapam, Deppe & Schiede.
Brachymenium brachypelma C. Müll. ex Ren. & Card., Bull. Soc. Roy. Bot. Beligique 31(1): 162. 1893. Protologue: Costa Rica. Chemin de la Piedra Blanca, Pittier 5562; Forêts du Barba, Pittier 5563.
Brachymenium condensatum Williams, Bryologist 26: 2. 1923. Protologue: Mexico. Michoacan, Patzcuaro, Dec. 21, 1891, Pringle 762 (MO).
Plants small, bright-green to yellowish green, in dense, shiny tufts or mats. Stems 5-30 mm long, epidermal cells rectangular, densely tomentose at base; rhizoids reddish brown, papillose, at times with red-brown, multicellular, globose propagula. Leaves crowded in rosulate tufts, 1.2–2.5 mm long, erect-appressed to imbricate not or rarely somewhat spirally twisted, spreading when wet, concave, ovate, oval, oblong to oblong-lanceolate; apices short acuminate, ending in a smooth or toothed capillary hair-point, yellowish at base, hyaline in upper ½, 0.4–1.0 mm μm long; margins not or weakly bordered below by 1-2 rows of somewhat narrower, elongate cells, upper marginal cells short-rectangular to somewhat elongate, entire or weakly serrulate, plane above, narrowly recurved below; costa ending below the apex in lower leaves, stoutly long-excurrent in upper leaves, ventral superficial cells at base quadrate to rectangular; cells firm-walled throughout, upper cells hexagonal to rhomboidal-hexagonal, 30–60 x 12 μm, basal cells often reddish near leaf insertion, quadrate to short-rectangular in up to 20 cells along the basal margin, 20–30 x 20 μm. Dioicous. Setae 15–25 mm long, yellowish red. Capsules 2.5–4.0 mm long, obovate-oblong, constricted at neck, erect to suberect; opercula 0.3–0.5 mm long, conic-apiculate; annuli compound, revoluble; exostome teeth reddish yellow, densely papillose, endostome yellowish, papillose, basal membrane to ½ the exostome teeth length, segments rudimentary, cilia rudimentary to absent. Spores 18–24 μm, papillose. Calyptra not seen.