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Genera

Andina

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Description:

Plants small to medium in size, growing in dense turfs, seldom scattered, blue-green to green or brown above, brown, reddish brown or blackish below. Stems erect, simple or branched, transverse section rounded-pentagonal, hyalodermis absent, sclerodermis present, central strand present; axillary hairs filiform, 36 cells long, with 1 brown basal cell and hyaline upper cells. Rhizoidal tubers absent. Leaves appressed, generally spirally wound around the stem, the upper sometimes twisted when dry, erect-patent to patent, sometimes spreading when moist, lanceolate, ovate, oblong-ovate, triangular, seldom oblong, infolded in the upper third or at the apex; lamina unistratose, red to orange with KOH; apex obtuse to rounded, seldom acute, cucullate, rarely apiculate; margins recurved to revolute from base or nearly so to the apex, occasionally plane at base, entire, unistratose or very rarely irregularly bistratose near the apex; costa percurrent or ending below the apex, not spurred; ventral surface cells of the costa in the upper half or two-thirds of the leaf differentiated as a unistratose, more rarely bistratose in patches, pad of cells, photosynthetic filaments or longitudinal lamellae; dorsal surface cells of the costa linear, sometimes shortly rectangular or quadrate distally, smooth; in cross-section at midleaf elliptic to rounded, with guide cells in 13 layers, band of ventral stereids differentiated or undifferentiated, band of dorsal stereids differentiated, semicircular in shape, without hydroids, dorsal surface cells differentiated, ventral surface cells forming a pad of bulging and papillose cells, lamellae or filaments, apical cell rounded to quadrate, smooth or papillose; upper and middle lamina cells rounded, subquadrate, quadrate or oblate, sometimes shortly rectangular, thick-walled, generally bulging, smooth or papillose, low, simple or more rarely bifurcate; juxtacostal basal lamina cells long-rectangular to quadrate, not inflated, usually thin-walled, smooth, sometimes forming a differentiated area; marginal basal cells rectangular, quadrate to oblate, sometimes shortly rectangular, generally thick-walled transversely, smooth. Gemmae multicellular, produced on branched stalks in leaf axils, abundant, generally spherical, sometimes elliptical, yellow-brown, smooth. Dioicous. Perigonia terminal; perigonial leaves scarcely differentiated. Perichaetial leaves not or scarcely differentiated. Seta erect, 1 per perichaetium, twisted to the left throughout, smooth, reddish brown to yellowish orange. Capsule erect, stegocarpous, exserted; theca cylindrical, brown; exothecial cells rectangular, slightly thick-walled; stomata at theca base, phaneroporous, annulus of 12 rows of cells; peristome of 32 filiform and spiculose-papillose teeth, almost straight to spirally twisted one turn, yellowish brown; basal membrane scarcely differentiated. Operculum rostrate to long-conic, yellowish brown. Calyptra cucullate, smooth, yellowish brown, naked. Spores spherical, yellowish brown, weakly papillose.

 


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