Streptopogon Wils. in Mitt., Kew J. Bot. 3: 51. 1851.
Plants small to medium-sized, in tufts or mats, green, reddish or yellowish green above, reddish brown below, corticolous. Stems smooth, erect, irregularly branched, central strand absent, cortical cells thin-walled, hyaline, uniform throughout; rhizoids thick, densely branched, with branches often at right angles. Axillary hairs 7–10 cells long, lower 1–3 cells brown. Leaves lanceolate, spathulate, or oblong, erect at base, keeled or concave, erect-incurved or crispate and contorted when dry, wide-spreading when wet; apices cucullate, acute, or acuminate; laminae unistratose; margins entire or serrate, bordered or unbordered; costa subpercurrent, percurrent or excurrent, guide cells and a single (dorsal) stereid or substereid band present, ventral surface layer of enlarged cells present or absent (the guide cells ventrally exposed); upper cells hexagonal, rhomboidal, or rectangular, firm-walled, at times bulging, smooth on both sides, basal cells rectangular, thin-walled, smooth, alar cells not differentiated. Dioicous or autoicous. Perichaetia and perigonia terminal. Setae smooth. Capsules exserted, cylindrical, erect, smooth; exothecial cells quadrate to rectangular, thin- or thick-walled; stomata in neck; opercula rostrate, annuli persistent, cells vesiculose or non-vesiculose; peristome teeth 16–32, filamentous, densely spiculose, twisted, basal membrane low or high. Spores granulate. Calyptrae conic-mitrate, papillose or smooth.