Monographs Details: Forsstroemia
Authority: Sharp, Aaron J., et al. 1994. The Moss Flora of Mexico. Part Two: Orthotrichales to Polytrichales. Mem. New York Bot. Gard. 69 (2)
Description:Genus Description - Plants of moderate size, in loose, dull or ± shiny, green, yellowish, or brownish mats. Primary stems creeping, stoloniform; secondary stems erect, sparsely to freely branched; paraphyllia none; pseudoparaphyllia broadly lanceolate. Leaves loosely erect or imbricate and smooth or ± plicate when dry, erect-spreading when moist, ovate-lanceolate to broadly oblong-ovate, gradually or abruptly narrowed to a short or long acumen; margins reflexed or ± revolute, entire or sometimes serrulate at the apex; costa single, strong, ending at or above the middle or slender and variable on the same plants (short, double, and sometimes nearly lacking or single and ending near the midleaf); cells smooth, thick-walled, rhombic to oblong-fusiform above, rounded- to oblate-quadrate in many oblique rows at the basal margins. Setae short, straight, smooth; capsules immersed to shortly exserted, erect, oblong-ovoid or oblong-cylindric, smooth; annulus none or narrow and fragmenting; operculum high-conic, acute or rostrate; exostome teeth narrowly lanceolate, translucent, white to yellowish or reddish, smooth or finely papillose above, sometimes perforate along the middle; endostome none or rudimentary. Spores spherical. Calyptrae cucullate, smooth, usually ± hairy.
The relationship of Forsstroemia may be outside the Leucodontaceae, if only because of an autoicous sexuality (at least in our species). The hairy calyptra is similar to that of Pterogonium, currently placed in the Leucodontaceae, but Stark (1985) has placed the genus in the Leptodontaceae, as did Buck (1980c). Buck (1989) included in the Leptodontaceae Leptodon, and Pseudocryphaea, in addition to Forsstroemia, Leucodontopsis he placed in the Pterobryaceae, as Hemicodium.