5: 257. 1852.
Stems short-creeping, 3–7 mm diam. Leaves usually many, arching to pendent. Petiole essentially absent to ca. 3–5 (–8) cm. Blade yellowish to dark green, elongate-linear, ± falcate, 30–60 × 0.5–1.5 cm, papery; base and apex long-attenuate; margins often slightly revolute. Veins obscure, primary-veins inconspicuous, slightly to strongly curved, areoles in 1–4 series between costa and margin, with free included veinlets. Sori in 1–2 rows on each side of costa.
Habitat: Epiphytic on oaks, pond apples, magnolias, and other rough-barked trees in hammocks and swamps in the everglade keys, substrate subacid
Elevation: 0 m
Fla., Mexico, West Indies, Central America, South America
In the flora Campyloneurum angustifolium occurs only in Collier County, Florida. It was reported earlier from Dade and Seminole counties.