Orthostichopsis tetragona (Sw. ex Hedw.) Broth.

  • 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

    Pterobryaceae

  • Scientific Name

    Orthostichopsis tetragona (Sw. ex Hedw.) Broth.

  • Description

    Species Description - Secondary stems glossy, golden to yellow-brown, 5-12 cm long. Leaves of secondary stems crowded, smooth, oblong to ovate, rounded to the insertion, abruptly acuminate, brittle-tipped, 2-3 x 1 mm; margins plane and entire; costa single, extending well up the leaf; apical cells fusiform, 25-32 x 5 µm; median cells linear, 65-75 x 2-5 µm; basal cells rectangular, 35 x 15 µm, red-brown; alar cells extending up margins by 15-30 cells, 10-15 µm, brownish. Branch leaves plicate, oblong-ovate, abruptly acute, 2-2.4 x 1 mm long; margins broadly inflexed above, serrate at the apex; apical cells 10-15 x 5-6 µm; median cells 50-63 x 2-3 µm; basal cells 20-25 x 5-7 µm; alar cells 5-10 x 10 µm, forming large, conspicuous groups. (Sporophytes not seen from Mexico.)

  • Discussion

    Fig. 527

    O. tetragona (Sw. ex Hedw.) Broth, in E. & P., Nat. Pfl. 1(3): 805. 1906.

    Hypnum tetragonumSw. ex Hedw., Sp. Muse 264. 1801.

    The plants have spirally ranked, plicate branch leaves with a single, elongate costa and well-marked alar cells. Two other species occur in Central America: O. auricostata (C. Müll.) Broth, has smooth leaves with short-acuminate tips and small and inconspicuous alar groups of cells. Orthostichopsis tortipilus (C. Müll.) Broth, has long-filiform leaf tips and small but well-defined alar groups, and its leaves are at most only weakly plicate.

  • Distribution

    Infrequent, on trunks and branches oftrees at low elevations; Chiapas, Oaxaca, Quintana Roo, Veracruz. Mexico to northern South America; West Indies.

    Mexico North America| Central America| South America| West Indies|