Sp. Musc. Frond. Suppl. 3(1,2): sub plate 246, fig. c. 1828.
Stems creeping, 1 mm wide across leafy stem, monopodial or sympodial, freely and irregularly branched; paraphyllia absent. Stem leaves loosely erect, heteromallous, not falcate-secund, not crowded, ovate to oblong-lanceolate, sometimes plicate, not rugose, 0.7–1.6 mm; base narrowly decurrent; margins nearly entire proximally, serrulate distally; apex acute to acuminate; costa double, 1/4–1/2 leaf length; alar cells differentiated; laminal cells scattered-prorulate. Branch leaves ovate to elliptic-lanceolate. [Capsule erect; operculum long-conic or obliquely rostrate; exostome teeth smooth proximally; endostome segments not perforate].
se United States, Mexico, se Asia, montane in warm temperate to tropical regions.
Species 3 (1 in the flora).
Generic concepts of Leptohymenium have varied greatly, but a constant critical character has been the erect, elongate capsules. The genus is circumscribed here in the restricted sense of V. F. Brotherus (1908, 1925) and J. R. Rohrer (1985).