Plants: of acidic rock, often volcanic, brownish. Alar cells not differentiated. Perigonial leaves broader and shorter than vegetative leaves. Perichaetial: leaves similar to vegetative leaves. Sexual: condition autoicous or rarely dioicous. Capsule: striate; annulus compound; peristome teeth papillose or absent. Calyptra: mitrate to sometimes sub-cucullate. North America, Central America (Honduras), South America (Brazil, Colombia), Europe, Asia, Australia.
Species 9 (2 in the flora). Brachydontium is a genus of tiny, brownish plants of acidic rocks with striate capsules and peristomes ranging from well developed to completely absent. The species in the flora are olive green to brownish, stems ca. 0.6–2 mm; leaves 0.5–2.5 mm, erect, in ± two apparent rows, lanceolate-subulate, obtuse, leaf margins nearly entire, costa filling the subula; and the columella is not developed. They grow sympatrically on Mt..