19. Pohlia nutans (Hedw.) Lindb. 黄丝瓜藓 huang si gua xian
Musci Scand. 18. 1879. Webera nutans Hedw., Sp. Musc. Frond. 168. 1801. Type: Europe.
Webera nutans var. hokinensis Besch., Ann. Sci. Nat., Bot., ser. 7, 15: 65. 1892.
Plants very small, ca. 5 mm high, dark green to yellowish brown, in loose tufts. Stems usually simple, sometimes branched at base, more or less twisted when moist. Leaves small below, becoming larger toward apex, ovate-lanceolate to lanceolate, 1.5–3.0 mm × 0.5–0.8 mm, often twisted at apex; margins sometimes recurved, serrulate above the middle; costae strong, curved above, keeled at the back, ending below the apex or nearly percurrent; median leaf cells linear-rhomboidal, 55–90 µm × 9–13 µm, somewhat thick-walled. Gemmae absent. Autoicous. Setae 1.5–2.5 cm long, orange-yellow; capsules pendulous when dry, inclined when moist, shortly club-shaped; neck shorter than urn, shrunk when dry; peristome double; endostome segments strongly perforate or split; basal membrane ca. 1/2 the length of teeth; cilia 2–3, nearly as long as the segments, nodose or appendiculate. Spores 16–20 µm in diameter, strongly papillose.