Dicranopteris flexuosa

Drooping Forked Fern is an evergreen native perennial fern in the Forking Fern family (GLEICHENIACEAE). It has been found at two locations in southern Mobile County near Delchamps, both in anthropogenically altered sites such as railroad banks and roadside ditches. It is a perennial from long-creeping, branched rhizomes that are covered in reddish-brown hairs. The leaves (fronds) are monomorphic, of apparently indeterminate growth, and thick and leathery in texture. The petiole is glabrous, stiff, brittle, and straw colored. The pinnae are opposite, in pairs, each pinna forked, with each fork bearing an arrested bud covered with tuft of hairs and pair of a stipule-like appendages. The pinnae are glabrous, thick and leathery in texture, with revolute margins, and glaucous below. The veins are 2--4-times forked. The sori are located on the underside of the pinnae and lack an indusium. Each sorus has 6--15 yellowish sporangia.

Drooping Forked Fern is a tropical species that sometimes becomes established in small populations near the coast. These populations are usually short lived. Because its occurrence in Alabama appears to be by natural means (most likely from spores transported north by tropical storms) it is considered native. However, both sites where it been discovered were anthropogenically altered into a vertical surface, an uncommon natural habitat in the outer coastal plain.—A. Diamond

Dicranopteris flexuosa was first collected in Alabama in 1913.  It was discovered by L.H. McNeill in a shallow railroad bank cut about 1.5 mi. E of Delchamps Station on Mon Louis Island in southern Mobile County (Maxon 1914).  The collection which is curated at the US Herbarium (Smithsonian) came from a single large plant in the vertical embankment cut. McNeill visited again on 15 May 1914 and made additional specimens one of which is deposited at the University of North Carolina Herbarium (NCU). The site was visited on 3 Dec 1916 by A.H. Howell whereupon he made additional specimens which are at the US Herbarium.  One of Howell's specimens includes a photo of the individual plant.  Graves (1920) visited the site in 1918 but found the site had been been altered and the plant was no longer present.  The species was not seen again in Alabama until 14 Jul 2020 when Gena Todia found it in the same general area but a different site (Keener et al 2024).--B.R. Keener