Pyrrhobryum Mitten, J. Linn. Soc., Bot. 10: 174. 1868.
[Greek pyrrho, flame-colored, tawny, red, yellowish-red, and bryon, moss]
Steven P. Churchill
Stems with exterior 2--3 rows of cells small, thick-walled, interior cells larger, moderately thick-walled; rhizoids often forming a dense tomentum below. Leaves distant [to crowded], linear-lanceolate [to broadly lanceolate], margin doubly-serrate to near base, apex acuminate; costa abaxially toothed [or smooth], transverse section with stereid cells well developed on both side of guide cells; juxtacostal basal cells often weakly differentiated, enlarged, short to rather long-rectangular, lax or not; medial and distal laminal cells uniform throughout, cells isodiametric, rounded to 4--6 sided, thick-walled, smooth; marginal laminal cells 2-stratose. Seta wiry. Capsule inclined to horizontal, usually curved, cylindric, becoming striate and flared at the mouth when deoperculate; exothecial cells quadrate- to rectangular-rounded, moderately thick-walled, somewhat weakly collenchymatous at base; stomates few at base, superficial.
Species 10 (1 in the flora): pantropical and south temperate areas.
The genus is characterized by the elongate stems, distal and spirally arranged broadly to narrowly lanceolate or linear-lanceolate leaves, doubly toothed, 2-stratose leaf margins, costa distally toothed abaxially, mostly isodiametric laminal cells alike to near base, and sporophyte positioned somewhat midway on stem or at the base.
Frahm, J.-P., K. Rembold, T. Röver and T. Schamell. 2003. Synopsis der Gattung Pyrrhobryum (Musci, Rhizogoniaceae). Trop. Bryol. 24: 115--127.