Acrostichum calomelanos Linnaeus, Sp. Pl. 2: 1072. 1753; Ceropteris calomelanos (Linnaeus) Link; Gymnogramma calomelanos (Linnaeus) Kaulfuss; Neurogramma calomelanos (Linnaeus) Diels.

Stipe 40-50 cm; lamina 2-pinnate, long oblong or oblong-lanceolate, 15-40 × 10-20 cm, thickly papery when dry, abaxially densely white farinose, adaxially grayish green, glabrous, base broadly cuneate, apex acuminate; rachis and costae purple-black, lustrous, glabrous, grooved adaxially; pinnae 16-20 pairs, oblique, with short, winged stalks; basal pair of pinnae not shortened, lanceolate, 10-15 × 2-5 cm, base slightly inequilateral; pinnules (or segments) 16-18 pairs, deltoid, ovate-lanceolate, or lanceolate, 1.1-1.4 × ca. 0.5 cm, base inequilateral, somewhat decurrent to costae, apex acute or acuminate; proximal pinnule margins serrate or lobed; lobes serrate or entire, with only 1 or 2 teeth at apex. Sori nearly confluent throughout abaxial pinnule surface when mature. 2n = 240.

Pityrogramma calomelanos is a cultivated ornamental plant of New World origins, which has become widely naturalized in the Old World.

Forest margins, stream banks; below 600 m. Hainan, Taiwan, S Yunnan (Lüchun) [Cambodia, Laos, Vietnam; Africa, South America].