Description from Flora of China
Terrestrial and climbing plants. Rhizome creeping or climbing, stout, terete, meristelic, with 40 or more vascular bundles in 3 circles, scaly only at apex; scales brown to blackish, orbicular, ovate, or ovate-lanceolate, margin uneven, peltate, caducous. Fronds distant, strongly dimorphic, stipe glabrous except when very young; lamina imparipinnate, leathery or stiffly papery, both surfaces glabrous; sterile pinnae broadly lanceolate, articulate to rachis (apical pinna not articulate), shortly stalked, with single gland on base of each costa, margin sharply toothed; veins anastomosing, forming single row of areoles along each side of costa, other veins free; fertile pinnae linear, lamina very reduced, margin entire. Sporangia acrostichoid, covering whole abaxial surface of fertile pinnae. Spores ellipsoid, with prominent tubercles on distal face. x = 37.
Stenochlaena is exceptional because of its distinct stele type. Ching (1978) gave it family status and placed it after the Acrostichaceae. Kramer (1990) treated it as a subfamily within the Blechnaceae based on its venation, stomata, spores, and gametophyte, which agree best with the Blechnaceae. Recent molecular data show that Stenochlaena forms a clade with species such as Blechnum indicum N. Burman and with Salpichlaena.
Six species: Africa, Asia, Australia, Pacific islands; one species in China.
(Authors: Dong Shiyong (董仕勇); Masahiro Kato)