Etymology Mono signifies single; chlamys recalls a kind of cloak worn by the ancient Greeks.

Description Rhizome: short-creeping, 4 mm diam., clump-forming, scales linear to linear-lanceolate, dark brown.
Frond: 40 cm high by 8 cm wide, deciduous, monomorphic, blade/stipe ratio: 3:2.
Stipe: purplish brown to reddish brown, polished, scaly at base, glabrous in upper portion, 2 mm diam., vascular bundles: 1 or 2.
Blade: 2-pinnate most commonly, but more at the base in mature specimens, ovate, with a terminal pinna similar to the terminal pinnules of the pinnae, papery, glabrous.
Pinnae: 4 to 6 pair, lanceolate, to 4 cm, anadromous in plan; pinnules wedge-shaped, to 12 mm; margins toothed at the far end; veins free, palmate.
Sori: oblong, mostly solitary in the center of the upper margin of the pinnule, indusium: false, inrolled margins, reniform, sporangia: reddish-brown.

Culture Habitat: dry cliffs or rocky slopes in open forests. Distribution: Japan, China, Korea. Hardy to -20°C, USDA Zone 6.

Distinctive Characteristics The single sorus may not be unique in the genus, but it is among temperate ferns.

Synonyms
Adiantum venustum var. monochlamys (Eaton) Luerss.
Adiantum veitchii Hance