Forsstroemia trichomitria (Hedw.) Lindb.

  • 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

    Leptodontaceae

  • Scientific Name

    Forsstroemia trichomitria (Hedw.) Lindb.

  • Description

    Species Description - Rather robust plants in whitish-green to pale yellowish brownish, slightly shiny tufts, subpinnately branched; branches straight, frequently stoloniform-attenuate. Leaves soft, crowded, erect and somewhat plicate when dry, erectspreading when moist, 1.2-2 mm long, concave, oblong-ovate to ovate-lanceolate, acute or short-acuminate; margins entire to slightiy serrulate at the apex, reflexed; costa very slender, single and extending above the leaf middle or shorter and often double to nearly lacking; upper cells oblong-fusiform (about 3.5:1), somewhat shorter at the apex, small, rounded-quadrate or transversely oblong, and opaque in numerous rows at the basal margins. Autoicous. Perichaetial leaves long-sheathing, usually reaching the urn and sometimes surpassing it. Setae 1-3.5 mm long; capsules immersed to shortly exserted, 1.5-1.8 mm long oblong-ovoid; annulus none; operculum stoutly and obliquely rostrate; exostome teeth whitish (becoming yellow with age), faintly roughened or nearly smooth; endostome adhering to the exostome, consisting of a very delicate and irregular, pale membrane, with segments sometimes visible as fragments. Spores 21-33 µm, very finely papillose. Calyptrae sparsely pilose.

  • Discussion

    Fig. 507

    F. trichomitria (Hedw.) Lindb., Ofvers. Forh. Svenska Vetensk.-19:605.1863.

    Pterigynandrum trichomitrion Hedw., Sp. Muse. 82. 1801.

    Forsstroemm mexicana Card., Rev. Bryol. 37: 6. 1910.

    As compared with F. producta, the plants are softer and paler, with leaves erect-spreading when moist and plicate, with longer cells and a variable costa.

    Stark (1985, 1987) considered several specimens from northeastern Mexico (Nuevo Le6n and Tamaulipas) and numerous others from a broad range in eastern North America to be possible hybrids between F. trichomitria and F. producta. The fact that F. producta is very rare and occupies very little ofthe range ofthe putative hybrid calls such a concept into question.

  • Distribution

    On the bark oftrees (on trunks, branches, and twigs), less commonly on logs or cliffs and boulders; Hidalgo, Nuevo Le6n, San Luis Potosf, Veracruz.— Northeastern Mexico; reported from the Dominican Republic; widespread in eastern North America (but more common southward). Stark (1985) included in the range southern Brazil, Uruguay, Paraguay, and Argentina, as well as Japan, eastern Asia, and Nepal.

    Mexico North America| Dominican Republic South America| North America| Brazil South America| Argentina South America| Uruguay South America| Paraguay South America| Japan Asia| China Asia| Mongolia Asia| South Korea Asia| North Korea Asia| Taiwan Asia| Nepal Asia|