Eucladium verticillatum (Hedw. in Brid.) Bruch & Schimp. in B. S. G., Bryol. Eur. 1:93. 1846; Weissia verticillata Hedw. in Brid., J. Bot. (Schrader). 1800 (1): 283. 1801.
Plants 5–20 mm high, dark green to yellowish green or brownish, in dense tufts. Stems erect, usually repeatedly branched. Leaves 1.0–2.5 mm long, slightly contorted when dry, erect-spreading when moist, oblong-ovate at the base, gradually narrowed toward the apex, narrowly lanceolate, rounded or blunt at the apex; margins plane, entire at the leaf base, serrate above the base; costa stout, percurrent; upper leaf cells small, green, rounded-quadrate, 8–10 µm wide, thick-walled, papillose; basal cells larger, irregularly rectangular, thin-walled, smooth, hyaline, marginal cells linear. Setae slender, straight, 7–11 mm long; capsules erect, elliptic-cylindrical; annuli poorly developed, of one row of cells; peristome teeth yellowish brown, slightly twisted counterclockwise, 2–3-divided to the middle, often irregularly perforate, densely papillose; opercula conic, obliquely rostrate. Calyptrae cucullate, smooth. Spores 8–13 µm in diameter, pale yellowish, smooth.
Chinese specimens examined: SHAANXI: Hu Co., P. J. Giraldi 1437 (H). XINJIANG: Begeda Mt., S.-E. Liu 3345 (PE).
Habitat: on rocks or thin soil over rocks; Distribution: China, Japan, India, northern Africa, Russia, Europe, and North America.
According to P.-C. Chen (1941) Brotherus’s report (1929) of Eucladium verticillatum from Yunnan province was based on misidentification of a specimen collected by Handel-Mazzetti (no. 359, H). The specimen is Gymnostomum rupestre Schwaegr. (= G. aeruginosum Sm.).
Illustrations: Zander 1993 (Pl. 10, figs. 1–9).