8. Ptychomitrium tortula (Harv.) Jaeg. 扭叶缩叶藓 niu-ye suo-ye xian
Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1872–73: 105. 1874. Didymodon tortula Harv. in Hook., Icon Pl. Rar. 1: 18. 1836. Glyphomitrium tortula (Harv.) Mitt., J. Proc. Linn. Soc. (London), Suppl. Bot. 1: 46. 1859. Type. Nepal: Wallich s.n.
Ptychomitrium mairei (Thér.) Broth., Symb. Sin. 4: 4. 1929. Brachysteleum mairei Thér., Bull. Soc. Sci. Nancy sér. 4, 3: 4. 1925. Type. “Colline de Ma-li-ouan, 2500 meters.” (isotype H).
Ptychomitrium speciosum Wils., Kew J. Bot. 9: 325. 1857, nom. nud.
Plants large, rather robust, (6–)9–15 cm high, green to reddish brown, in loose tufts. Stems branched; central strand well developed. Leaves 5.5–7.0 mm long, strongly crisped and contorted, somewhat shining when dry, erect-spreading to wide-spreading when moist, gradually narrowed from a broadly oblong, distinctly plicate base to lanceolate or linear-lanceolate acumen, strongly keeled and somewhat secund above; margins recurved below, irregularly toothed above, each tooth consisting of several cells; costa single, strong, becoming narrow above, subpercurrent or ending just below the apex; upper leaf cells irregularly quadrate, 6–8 µm wide, with slightly thickened walls; median cells short-rectangular to rectangular, 8–11 µm × 5–6 µm, strongly sinuose; basal cells elongate, 18–39 µm × 3–4 µm, with strongly sinuose walls. Autoicous. Perichaetial leaves similar to the upper stem leaves, but slightly larger. Setae straight, yellow or reddish brown, 5–7 mm long, twisted above; capsules often 2–4 per perichaetium, erect, oblong-ellipsoid, yellowish brown, ca. 1.5 mm long; annuli undifferentiated; peristome teeth elongate, linear, yellowish brown, forked in the upper part, sometimes perforated in the middle, densely and finely papillose; opercula with a long beak. Calyptrae mitrate, reaching the middle of capsule, longitudinally plicate, lobed at the base. Spores spherical, nearly smooth.