41. Fissidens protonematicola Sak.   原丝凤尾藓   yuan-si feng-wei xian

Bot. Mag. (Tokyo) 47: 741. 1933 (‘protonemaecola’). Type. Japan: Kyushu, 23 VI 1931, Y. Doi s.n., in herb. K. Sakurai, no. 1680 (holotype MAK).

Fissidens gemmaceus Herz. & P. de la Varde in Herz. & Nog., J. Hattori Bot. Lab. 14: 55. 1955. Type. China: Taiwan, G. H. Schwabe 17 p.p. (holotype JE).

 

Plants minute, protonemata persistent. Leafy stems very short, 0.6–0.8 mm long, 0.2–0.4 mm wide; axillary hyaline nodules not differentiated; central strand not developed, in cross section, stems consisting of large cells with thin walls. Leaves extremely small, in 1–3 pairs, 0.4–0.6 mm × 0.1–0.2 mm; upper leaves ovate to ovate-lanceolate, with vaginant laminae, acute to obtuse at apex; lower leaves reduced to scales, without distinct vaginant laminae; base of dorsal laminae wedge-shaped; costa ending a few cells below leaf apex; margins crenulate; cells of apical laminae quadrate, rectangular to irregularly hexagonal, 23–35(–45) µm long, thin-walled, almost smooth, the cells becoming longer toward the base of vaginant laminae. Rhizautoicous. Male shoots much smaller than female ones. Archegonia terminal, ca. 180 µm long. Setae 1.5–2.5 mm long, smooth; capsules erect, symmetrical, urns 0.3–0.4 mm long; opercula rostrate, ca. 0.3 mm long; exothecial cells quadrate to rectangular, thin-walled; peristome teeth ca. 0.2 mm long, 35 µm wide at base. Calyptrae mitrate, ca. 0.25 mm long, smooth. Spores not seen.