光滑方杆蕨 guang hua fang gan jue

Plants ca. 85 m tall. Rhizomes creeping, glabrous. Fronds sparse; stipes ca. 35 cm, bases dark brown, distally stramineous, grooved adaxially, glabrous throughout; laminae oblong, ca. 50 × 20 cm, slightly tapering to bases, pinnate-pinnatifid, acuminate and pinnatifid at apices; pinnae ca. 30 pairs, opposite, sessile, proximal 2 pairs slightly shortened, 7-10 cm, tapering to bases, third pair of pinnae linear-lanceolate, ca. 12 × 1.5 cm, bases widest, truncate, pinnatifid nearly to costae, apices acuminate; segments ca. 35 pairs, spreading, proximal pair longest (9-11 mm), distal ones triangular-lanceolate, ca. 7 × 3 mm, entire and pointed at apices. Veins evident, veinlets 9 or 10 pairs per segment, proximal pair reaching margins above sinuses. Laminae herbaceous, green when dry, glabrous except for adaxially along grooves of rachises. Sori orbicular, attached at bases of veinlets and in one row on each side of costules; indusia bearing acicular hairs. Sporangia each with 1-3 acicular hairs near top.

● Mixed forest margins in valleys; 1500-1800 m. NE Yunnan.