鲁山对囊蕨 lu shan dui nang jue

Basionym: Athyriopsis lushanensis J. X. Li, Acta Phytotax. Sin. 26: 162. 1988.

Plants summer-green. Rhizome slender, creeping, ca. 3 mm in diam., apex with pale brown, broadly lanceolate thin scales; fronds separate. Fertile frond up to 60 cm; stipe black at base, upward light stramineous, 10-30 cm, ca. 1 mm in diam., base sparsely scaly, upward with sparse narrowly lanceolate, pale brown scales and nodose hairs; lamina broadly lanceolate, up to 40 × 12 cm, acuminate at apex; free pinnae up to 15 pairs, mostly alternate, spreading, lanceolate, pinnatipartite, apex acute or rounded; basal pinnae larger, up to 7 × 2.5 cm, shortly stalked, other pinnae sessile; pinna lobes up to 8 pairs, rectangular or oblong, acroscopic basal lobe larger, margin sparsely shallowly crenate, apex truncate or rounded; veins per lobes pinnate with less than 4 pairs of veinlets, ascending, simple, rarely forked. Lamina thinly herbaceous, pale green when dry; rachis with sparse yellow-brown scales and nodose hairs, costae with sparse nodose hairs. Sori shortly linear, 1-3 pairs per lobe, single, medial or subbasal, double on acroscopic basal veinlets; indusia yellow-brown, membranous, glabrous, persistent, margin shallowly erose, incurved when young. Spores suborbicular in polar view, semicircular in equatorial view, perispore with irregular tuberculate ornamentation.

● Shandong (Lushan).