1. Helodium paludosum (Aust.) Broth. 狭叶沼羽藓 xia-ye zhao-yu xian
Nat. Pflanzenfam. I(3): 1009. 1908. Elodium paludosum Aust., Musc. Appalach. 301. 1870. Hypnum paludosum Sull., Musci. Allegh. 6. 1846, hom. illeg. Type. U.S.A. Ohio, Columbus.
Plants rather robust, up to 6 cm long, yellowish to yellowish brown, in lax patches. Stems creeping and spreading, regularly pinnately branched; branches ca. 5 mm long; central strand undifferentiated; paraphyllia densely growing on stems and branches, usually filamentous, irregularly branched. Stem leaves appressed when dry, erect-spreading when moist, broad and concave at base, oblong to ovate, gradually acuminate, ca. 1.0–1.5 mm long, slightly plicate and decurrent; median leaf cells narrowly hexagonal, ca. 15–30 µm × 5 µm, thick-walled, finely papillose near the upper corners; apical cells elongate-rhomboidal. Autoicous. Perichaetial leaves ovate-lanceolate to lanceolate at the base, slenderly lanceolate toward apex. Sporophytes not seen.