Fissidens acutus Jaeg., Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1874–75: 93. 1876. Fissidens mangarevensis Mont., Ann. Sci. Nat. Bot., sér. 3, 4: 113. 1845. Fissidens pungens Sull. & Lesq., Proc. Amer. Acad. Arts Sci. 4: 276. 1859, hom. illeg., non Fissidens pungens Hampe & C. Müll., Linnaea 26: 502. 1855. Type. China: Hong Kong, on rocks in shaded ravines, Wright s.n. (holotype FH).

Plants small, yellowish green to dark green, growing in dense tufts. Leafy stems simple or sometimes branched, 3.3–7.0 mm long, 2.5–3.0 mm wide; axillary hyaline nodules not developed; central strand slightly differentiated. Leaves in 4–12 pairs, lowest ones small and distantly arranged, larger and densely arranged upwards; middle to upper leaves narrowly lanceolate, 1.6–2.8 mm × 0.2–0.3 mm, acute at apex; base of dorsal laminae wedge-shaped or rarely rounded; vaginant laminae ca. 1/2 the leaf length, unequal; costa stout, flexuous, ending a few cells below apex; margins serrulate; cells of apical and dorsal laminae rounded to rounded-hexagonal, 7–15 µm long, more or less thick-walled, distinctly mammillose except those at extreme leaf apex; cells of vaginant laminae similar to those of apical and dorsal laminae, but less mammillose and with thicker walls. Autoicous. Male inflorescences axillary. Female inflorescences terminal. Perichaetial leaves not clearly differentiated. Archegonia 300–400 µm long. Setae ca. 6 mm long, smooth; capsules erect to slightly inclined, symmetrical or slightly asymmetrical; urns oblong-ovoid, ca. 0.4 mm long; opercula long rostrate, ca. 0.45 mm long; peristome teeth ca. 0.3 mm long, 35 µm wide at base. Calyptrae campanulate, ca. 1.0 mm long. Spores 10–14 µm in diameter.

Type. New Zealand: North Island, Bay of Islands, sine coll.

Chinese specimens examined: FUJIAN: Wuyi Shan (Mt.), D.-K. Li & C.-H. Gao 11904 (SHM, SYS). GUANGDONG: Cong-hua Co., P.-J. Lin 44 (IBSC, SYS); Ding-hu Shan (Mt.), Z.-H. Li & P.-J. Lin 038 (IBSC, SYS), Redfearn et al. 34395 (MO); Feng-kai Co., L. Sun & J.-L. Zhang 115 (SYS); Liang-ping Co., P.-J. Lin 1531 (IBSC, SYS); Nan-kun Shan (Mt.), Z.-H. Li 220 (SYS). HAINAN: Jian-feng-ling (Mt.), P.-C. Chen 766 (PE. SYS); Le-dong Co., Redfearn 35954 (MO). HUNAN: Liu-yang Co., 1974 Team 283 (IBSC, SYS). SICHUAN: Liang Shan (Mt.), G.-C. Zhang & T. Cao 21847 (IFSBH, SYS); Ya-an Co., C. Gao 17154 (IFSBH, SYS). XIZANG: Cha-yu Co., M.-Z. Wang 8193c (PE, SYS). Yunnan: An-ning Co., Redfearn 32335 (HKAS, MO).

Habitat: mostly on soil, rarely on rocks; Distribution: China, Japan, Malaysia, southwestern Pacific, Australia, New Zealand, South and Central America, Mexico, and West Tropical Africa.

Illustrations: Z.-H. Li 1985 (Fig. 18, a–h, as Fissidens mangarevensis).