39. Fissidens perdecurrens Besch. 延叶凤尾藓 yan-ye feng-wei xian
J. Bot. (Morat). 12: 293. 1898. Type. Japan: Honshu, U. Faurie 14088 (isotype H-BR).
Plants medium-sized to large, dark green, creeping, rigid. Leafy stems simple or branched, 12–35 mm long, 3.0–3.3 mm wide; axillary hyaline nodules differentiated, but neither large nor transparent; cortical cells small and thick-walled, central strand not differentiated. Leaves in 20–24 pairs, densely arranged, lowest leaves small; middle to upper leaves much larger, narrowly lanceolate, ca. 1.6–2.3 mm × 0.3 mm, acute at apex; base of dorsal laminae wedge-shaped, decurrent; vaginant laminae ca. 1/2 or less of the leaf length, often equal; margins crenulate; costa stout, obscure, percurrent or ending a few cells below leaf apex, two rows of large, rectangular to narrowly rectangular cells, more or less clearly visible through surface cells from middle to upper portion of costa, in cross section, apical and dorsal laminae 1–2 cells thick at margin, 3–4 cells thick near costa, one cell thick for most of the vaginant laminae; cells of apical and dorsal laminae quadrate to irregularly hexagonal, 7–11 µm long, slightly mammillose, moderately thick-walled; cells of vaginant laminae similar to those of apical and dorsal laminae, but less mammillose, with thicker walls toward base. Dioicous. Female inflorescences axillary. Perichaetial leaves differentiated, linear-lanceolate, much shorter and narrower than stem leaves. Archegonia 315–350 µm long. Sporophytes not seen.