Breutelia subarcuata (C. Müll.) Schimp. ex Besch., Mém. Soc. Sci. Nat. Cherbourg 16: 204. 1872. Bartramia subarcuata C. Müll., Syn. Musc. Frond. 2: 617. 1851. Protologue. Mexico. Pico de Orizaba, alt. 11000 ped.: Liebmann.
Plants robust, in loose or dense, somewhat glossy, yellowish‑green to brownish yellow tufts, to 11 cm high. Stems red, hyalodermis and central strand present, moderately to densely tomentose below; rhizoids reddish brown, lightly papillose. Leaves 3–5 x 1.2–1.9 mm, closely spaced, secund to subfalcate, rugose, at times twisted when dry, erect-spreading to secund when wet, curved-falcate, ovate to broadly lanceolate, strongly plicate at base, not decurrent; apices slenderly acuminate; margins recurved below, plane above midleaf, serrulate; costae percurrent to shortly excurrent; leaf cells porose or smooth-walled, papillose at lower ends above, from either end below, upper cells linear-elongate, thick‑walled, 17–75 x 5–7.5 μm, basal cells linear-elongate, 37–88 x 5 μm, thick-walled, alar region with 4–9 rows of enlarged, firm-walled or inflated cells at basal angles, often extending up the basal margins, intra-alar cells hyaline or orange, straight-walled, length to width ratio 1–2:1. Dioicous. Sporophytes not seen. “Setae 4–9 mm long, arcuate, capsules subglobose, 3–3.5 mm long x 2.5 mm wide, irregularly rugulose to nearly smooth when dry, peristome inserted below the mouth, exostome teeth lanceolate, reddish orange, 480–520 μm long, granulose-papillose, endostome pale yellow, nearly equally the exostome, faintly papillose, spores subreniform, areolate-tuberculate, 30–33 μm long x 24–27 μm wide” (Griffin 1984).