华东二形凤尾藓

Fissidens geminiflorus var. nagasakinus (Besch.) Iwats., J. Hattori Bot. Lab. 32: 272. 1969. Fissidens nagasakinus Besch., J. Bot. (Morat) 12: 292. 1898. Fissidens irroratus Card., Beih. Bot. Centralbl. 19(2): 99. f. 5. 1905. Type. China: Taiwan, Kushaku, 6 VI 1903, U. Faurie 124 (isotype H-BR).

Plants medium-sized to rather large, green to dark green. Leafy stems prostrate, simple or branched, 8–42 mm long, 2.7–3.1 mm wide; axillary hyaline nodules often slightly differentiated; central strand not differentiated. Leaves in 16–52 pairs, usually loosely arranged, crisped when dry; lower leaves often decayed or fragile; middle and upper leaves lanceolate to narrowly lanceolate, 1.8–2.5 mm × 0.3–0.4 mm, acute at apex; base of dorsal laminae wedge-shaped, rarely rounded, clearly decurrent; vaginant laminae 1/2 –3/5 the leaf length, equal or slightly unequal; costa stout, percurrent, a row of cells at both sides of costa often enlarged, irregularly quadrate to rectangular, smooth, more or less pellucid; margins serrulate; cells of apical and dorsal laminae quadrate to rounded-hexagonal, 7–13 µm long, moderately thick-walled, mammillose, obscure; cells of vaginant laminae similar to those of apical and dorsal laminae, but larger, less mammillose and with thicker walls; in cross section laminal cells one cell thick, except near costa. Dioicous. Female inflorescences bud-like, axillary. Perichaetial leaves well differentiated. Archegonia 284–355 µm long. Male inflorescences and sporophytes unknown.

Type. Indonesia: Java.

Chinese specimens examined: FUJIAN: Yong-chuan Co., D.-K. Li 10655 (SHM, SYS). GUANGDONG: Feng-kai Co., L. Sun & J.-L. Zhang 61 (SYS); Shi-xing Co., P.-J. Lin & Y.-Y. Yang 5128 (IBSC, SYS). HAINAN: Jian-feng-ling (Mt.), Z.-H. Li 85–143, 85–146 (SYS). JIANGSU: Yi-xing Co., D.-K. Li 233 (SHM, SYS). Sichuan: Luo Shan (Mt.), S.-M. Yu 419 (HKAS, NICH). TAIWAN: Tai-bei Co., M.-J. Lai 1298 (H); Tao-yuan Co., M.-J. Lai 9416 (H, MO). YUNNAN: Gong-shan Co., M.-Z. Wang 9714 (PE, SYS). ZHEJIANG: De-qing Co., P.-C. Wu 1267 (MO, PE); Lin-an Co., P.-C. Wu 8093 (MO, PE); Pu-tuo Shan (Mt.), D.-K. Li 7025 (SHM, SYS); Yan-tang Shan (Mt.), D.-K. Li 7921 (SHM, SYS).

Habitat: on wet rocks; Distribution: China, Japan, Indonesia, and the Philippines.

This species can be distinguished from its closely related species, Fissidens perdecurrens, by the unistratose laminae, which are more transparent, often crisped when dry, and by its usually loosely arranged leaves.

Illustrations: Pl. 79, figs. 1–15.