1b. Drepanocladus aduncus var. kneiffii (Schimp.) Mönk. 镰刀藓直叶变种 lian dao xian zhi ye bian zhong
Laubm. Eur. 755. 1927. Hypnum kneiffii (Schimp.) Schimp. in Wilson, Bryol. Brit. 390. pl. 18. 1855. Hypnum aduncum var. kneiffii (Schimp.) Schimp., Musci Eur. Nov. 3–4, Mon. 1. pl. 1. 1866. Hypnum aduncum subsp. kneiffii (Schimp.) Renauld, Rev. Bryol. 8: 74. 1881. Amblystegium kneiffii Schimp. in B.S.G., Bryol. Eur. 6: 61. pl. 573. 1853. Type: Europe.
Plants rather robust, yellowish green or dark green, in loosely caespitose mats. Stems prostrate, 20–60 cm long, irregularly pinnately branched; in cross section cortical cells small, thick-walled, in 1–2 layers; central strand weakly differentiated. Stem leaves erect or falcate-secund, broadly lanceolate, gradually narrowed to a long acuminate apex; margins plane, entire; costae reaching ca. 1/2 the leaf length or beyond; median leaf cells linear, thin-walled; basal cells broader, shorter; alar cells hyaline or yellowish brown, distinctly differentiated, in several regular rows, extending close to costa at leaf base, forming well-defined auricles. Sporophytes not seen.