Naturalized Holly fern

Latin falcatus, sickle-shaped, in reference to the shape of the pinnae.

Rhizomes erect, short, densely scaly. Fronds 30-60 cm long. Stipes straw-colored, densely scaly at bases, sparsely scaly distally, scales brown to dark brown, ovate-lanceolate, membranous. Blades 1-pinnate, ovate-lanceolate, coriaceous; rachises with many light brown hairs and hairlike scales. Pinnae 5-14 pinna pairs, short-stalked, falcate to ovate-falcate, 7-13 cm long, very glossy dark green above, lighter green below, coriaceous, adaxial surface with many light brown hairs and hair-like scales, bases elliptic to rounded, mar. gins entire or undulate, never serrate, tips acuminate. Veins reticulate, forming areoles with included veinlets, raised abaxially, obscore adaxially. Sori plentiful, round, small, about 1 mm diam., borne on veins in areoles. Indusia peltate.

Escaped in dry, mesic, to wet forest floors and valleys, near sea level to 1,525 m, all major islands. It prefers windward sea cliffs.

Cyrtomium falcatum is native to eastern Asia, including China, South Korea, Japan, the Ryukyus, and Taiwan and is very popular in cultivation because of its glossy, dark green fronds. A hybrid between C. caryoti-deum and C. falcatum exists in horticulture, but has not been seen in the wild in Hawai'i. Cyrtomium falcatum was first noted to be naturalized in Hawai'i in 1928 on the cliffs and gulches above Kalaupapa, Moloka 'i.

Cyrtomium falcatum differs from C. car· yotideum by having more pinna pairs (5-14), blades that are a darker glossy green above, pinnae margins entire or undulate but never serrate or auriculate, and raised veins on the lower surfaces of pinnae.