Diplazium kanayamaense

Description. Terrestrial summergreen fern. Rhizomes: creeping, non-branched, black, 10 - 15 x 0.5 - 0.8 cm in diam., closely set with roots and persistent, densely clothed with old stipe bases, glabrous; fronds: 2 - 5 per rhizome; stipes: purplish-green, 8 - 11 x 0.2 - 0.3 cm in diam., glabrous in middle to upper sections, sparsely clothed with dark brown scales (2.0 - 4.0 x 0.5 - 1.0 mm, with small projection on margin) of basal sections, lanceolate; blades: fresh green on adaxial surface, 1 - pinnate pinnatifid, 1 - pinnate at the apex, 15 - 26.5 x 8 - 23 cm, ovate; rachises: purplish-green, glabrous; pinnae: 9 - 10 pairs, ascending, lanceolate, alternate or opposite, petiolated (2 - 4 mm long), serrate to lobed, curved from base to apex, acute at the apex, sessile near the apex of blades, widely spaced, lowest pair slightly reduced or the same as second, second lowest pair usually largest, 15 - 17 cm x 1.5 - 3 cm; pinnules: alternate, 9 - 10 pairs on the basal sections of the blade, reduced distally, ovate to lanceolate, entirely to shallowly serrated, acute at apex in basal part of blade, obtuse at the apex in the middle section of blades, vein-free, single or double, close to or reaching to the margin, 5 - 7 pairs in the middle lobe; the most basiscopic pinnules on the lowest pinnae: occasionally absent, clearly short, independent from the costa, 2 - 10 mm x 1.5 - 4.0 mm; sori: long linear- or J-shaped, 1.0 - 3.0 mm long, on the middle of veinlets, 4 - 10 pairs per ultimate segment, persistent; indusia: cloudy white or brown, same shape as sori, entire, persistent; spores: absent or irregular-shaped, abortive.