Fissidens microserratus Sak., Bot. Mag. (Tokyo) 47: 738. 1933.

Plants small, green to dark green. Leafy stems usually simple, rarely branched, 1.3–4.8 mm long, 0.8–1.6 mm wide; axillary hyaline nodules indistinctly differentiated; central strand not differentiated. Leaves in 4–11 pairs, densely arranged; the lowest leaves much smaller; middle to upper leaves larger, narrowly lanceolate, 0.9–1.5 mm × 0.2–0.3 mm, narrowly acute; base of dorsal laminae wedge-shaped; vaginal laminae 1/2 the leaf length; costa yellowish, pellucid, percurrent to shortly excurrent; margins finely crenulate to serrulate; limbidia present only on lower one-half of the vaginant laminae of upper and perichaetial leaves; limbidia composed of 2–3 rows of cells, one cell thick; cells of apical and dorsal laminae quadrate to hexagonal, 5–9 µm wide, dark, obscure, pluripapillose, thin-walled; cells of vaginant laminae similar to those apical and dorsal laminae, but longer, thick-walled and with fewer papillae to smooth. Autoicous to rhizautoicous. Archegonia 175–192 µm long. Setae 1.8–3.5 mm long, smooth, geniculate at base; capsules cylindrical, somewhat asymmetrical; urns 0.4–0.5 mm long; exothecial cells quadrate, thin-walled, with thickened corners; opercula long rostrate, ca. 0.4 mm long; peristome teeth 0.24–0.28 mm long, 30–33 µm wide at base. Calyptrae campanulate, ca. 0.3 mm long. Spores 7–9 µm in diameter.

Type. New Caledonia: A. Le Rat 948 (lectotype H-BR).

Chinese specimens examined: GUANGDONG: Lian-ping Co., P.-J. Lin s.n. (IBSC, SYS). HAINAN: Wu-zhi Shan (Mt.), Z.-H. Li 2075 (H, SYS). LIAONING: Feng-cheng Co., C. Gao 5983 (IFSBH, SYS). TAIWAN: Tai-bei Co., C.-C. Chuang & Schofield 30 (H, UBC). YUNNAN: Kun-ming City, Koponen 37446, 37870 (H, SYS); Meng-hai Co., Magill et al. 7910 (MO); Meng-la Co., Magill et al. 7587 (MO).

Habitat: on sandy soil, rarely on tree bases; Distribution: China, Korea, Japan, New Caledonia, and Australia.

Illustrations: Pl. 84, figs. 1–14.