Monographs Details: Hemiragis
Authority: Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.
Description:Genus Description - Plants robust, in lustrous, yellow-green (rarely bright-green) to golden-brown, often large and extensive mats or ± tufts. Stems creeping to ± erect, ± regularly to irregularly pinnately branched, the branches not differentiated, evenly foliate; in cross-section with a hyalodermis over medium-sized thick-walled cells surrounding larger thin-walled cells, central strand none; rhizoids tufted on lower surfaces of stems, smooth; pseudoparaphyllia foliose but branches mostly arising from leaf axils; axillary hairs 2-celled, with a short brown basal cell and an elongate hyaline distal cell. Leaves crowded, not contorted, ± falcate, isophyllous, narrowly long-triangular, gradually acuminate, plicate; margins not bordered, serrate to serrulate almost throughout, plane to erect; costa double, slender, ± parallel or gradually and slightly converging throughout; cells linear, smooth, thick-walled, porose, becoming shorter and broader at the colored insertion, often with stem cells stripping off with dissection; alar cells not differentiated. Asexual propagula none. Autoicous. Perichaetia large, conspicuous; leaves spreading from an erect base, broadly oblong, abruptly tapering to a long, loriform acumen; margins subserrulate, plane; costa double, single or absent; cells linear, smooth, thick-walled, porose, becoming shorter, broader and colored across the insertion. Setae very long, smooth or slightly roughened above, reddish; capsules inclined to horizontal, cylindric, asymmetric; exothecial cells short-rectangular, thin-walled at surface, with collenchymatous thickenings at comers below the surface; annulus not differentiated; operculum conic-rostrate; columella almost as long as the urn, broadly cylindric; peristome double, attached at the mouth, exostome teeth narrowly triangular, bordered, not shouldered, on the front surface with a median furrow, the plates cross-striolate with overlying papillae below, papillose above, slightly trabeculate at back; endostome with a fairly high basal membrane, segments keeled, narrowly perforate, with baffle-like crosswalls, ca. as long as the teeth, cilia none. Spores spherical, finely papillose. Calyptrae mitrate, lobed at base, sparsely hairy, smooth except somewhat roughened at extreme apex.
Discussion:Hemiragis (Brid.) Besch., Ann. Sci. Nat. Bot. VI, 3: 242. 1876; Leskea subgen. Hemiragis Brid., Bryol. Univ. 2: 334. 1827; Hookeria sect. Hemiragis (Brid.) Mitt., J. Linn. Soc., Bot. 12: 335. 1869.
Discussion. Hemiragis is characterized by its robust size with ± triangular, very plicate leaves with slender, double costae. The cells are linear, thick-walled and porose. In aspect it resembles a large Diploneuron but the slender costae that do not fuse above readily separate it. The exostome is furrowed and cross-striolate. The endostome has a relatively high basal membrane and keeled segments with baffle-like crosswalls. The mitrate calyptra is lobed at base and only sparsely hairy.
Hemiragis is a monospecific genus confined to Central America, the West Indies, and northern South America. It is probably most closely related to Brymela, but the suberect stems and plicate leaves will readily distinguish it.