2. Pterygoneurum subsessile (Brid.) Jur., Die Laubmoosflora von Oestrreich-Ungarn. 1882; Gymnostomum subsessile Brid., Muscol. Recent. Suppl. 1: 35. 1806.
Plants 2–4 mm high, grayish green to yellowish green, gregarious or in thin tufts. Stems erect, simple or occasionally branched at the base. Leaves appressed when dry, weakly erect-spreading when moist, oblong ovate to ligulate or elliptic, strongly concave, 2–3 mm long with the awn; margins entire or serrulate at or near the base of the awn, plane or weakly incurved; costa rather stout, excurrent, ending in a long awn, nearly twice as long as the leaf length, denticulate; with 2–4 rows of green lamellae on the ventral side of costa; upper leaf cells quadrate to rounded hexagonal, 10–14 µm in diameter, moderately thick-walled, smooth or with simple or blunt C-shaped papillae; basal cells rectangular, 23–40 µm x 13–16 µm, thin-walled, smooth. Setae 0.3–0.5 mm long; capsules immersed, subhemispheric to ovoid; annuli none; opercula conic-rostrate, with a short, straight beak; peristome teeth absent. Calyptrae mitrate, smooth. Spores 35–38 µm in diameter, brownish, finely papillose.
Type. Germany: Jena, Flörke s.n.
Chinese specimens examined: NEI MONGOL: Hohhot City, Z.-G. Tong 2525 (PE). XINJIANG: Burgin Co., Whittemore et al. 4753 (MO); Altai Mt., Qing-he River valley, Whittemore et al. 4605c, 4630 (MO).
Habitat: on soil or thin soil over rocks; Distribution: China, Mongolia, Russia, Central Asia, Europe, North America, and northen Africa.
Illustrations: X.-L. Bai 1997 (Pl. 60, figs. 7–12).