Plants: small to large, green, yellow-green, golden yellow, or golden brown, glossy or dull. Stems: 0.3–5 cm, not complanate-foliate, irregularly branched. Leaves: erect-spreading to falcate-secund, often homomallous, oblong-lanceolate, oblong-ovate, or ovate; margins entire; apex acute to acuminate; ecostate or costa double; alar cells elongate, somewhat to strongly enlarged and inflated, pigmented or rarely unpigmented, walls thin, region in 1–several rows, middle lamella not apparent, supra-alar cells differentiated; laminal cells rhomboidal, elliptic, or flexuose, smooth. Sexual: condition autoicous [dioicous]. Seta: 0.4–2 cm. Capsule: inclined to horizontal or rarely erect, short-cylindric; exothecial cell walls collenchymatous; operculum rostrate. Nearly worldwide, temperate to pantropical regions.
Species ca. 50 (4 in the flora). As W. R. Buck (1998b) has noted, Sematophyllum is a catch-all genus in need of a world monograph; however, the four North American species are reasonably treated in Sematophyllum. The genus is confined to eastern forests in the flora area, and introduced to California, where it is rare. The plants have red-brown stems with foliose pseudoparaphyllia; the medial laminal cells are rhomboidal to flexuose.