Monographs Details: Trichosteleum
Authority: Sharp, Aaron J., et al. 1994. The Moss Flora of Mexico. Part Two: Orthotrichales to Polytrichales. Mem. New York Bot. Gard. 69 (2)
Family:Sematophyllaceae
Scientific Name:Trichosteleum
Description:Genus Description - Plants slender to medium-sized, in thin, yellowish or brownish-green mats. Stems creeping, freely but irregularly branched branches sometimes ± flattened. Leaves erect-spreading to ± falcate-secund, sometimes obscurely complanate concave lanceolate to ovate-lanceolate, acute or acuminate; margins sometimes recurved, subentire to serrate; costa short and doubleupper cells linear-rhomboidal to fusiform, thin- to thick-walled, unipapillose over the lumina, except at the margins- alar cells conspicuously large and oblong-inflated, usually yellow. Autoicous. Perichaetial leaves lance-acuminate Setae often rather short (about 3-10 mm long), curved at the apex and often roughened just below the capsule; capsules oblong-cylindric to obovoid; operculum slenderly long-rostrate; exothecial cells collenchymatous; exostome teeth cross-striolate below with a median zigzag line (or often furrowed), trabeculate; endostome with a high basal membrane, keeled, papillose segments and 1-2, sometimes mdimentary cilia. Calyptrae cucullate, smooth, or sometimes roughened above, naked.

Discussion:In addition to the collenchymatous exothecial cells and the conspicuously inflated alar cells, the single papillae over the lumen of most, if not all leaf cells is a distinctive generic character. The peristome is generally furrowed.