Monographs Details: Hygrohypnum
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:Campyliaceae
Scientific Name:Hygrohypnum
Description:Genus Description - Plants slender to moderately robust, in green, yellow, or red-gold, dense mats, sometimes shiny. Stems creeping, often denuded with age, irregularly branched. Leaves generally crowded, imbricate to spreading, often secund, concave (sometimes strongly so and ± cucullate at apex), smooth or weakly plicate, oblong-lanceolate and acuminate or broadly oblong-ovate to subcircular and blunt to rounded or abmptly short-pointed at the apex; margins erect (or sometimes incurved above), entire or sermlate; costa often variable on the same plants, generally unequally forked and usually short and weak, rarely single and sometimes nearly percurrent; cells smooth, linear-flexuous, often short and rhombic at the extreme apex, mostly yellow or orange but otherwise scarcely differentiated at the middle ofthe insertion; alar cells subquadrate or oblong, hyaline or colored, sometimes inflated in small, well-marked groups. Perichaetial leaves erect, elongate, generally striate, with costa short, single or forked.

Discussion:

The plants grow on wet rocks in or along streams. The leaves, broad and shortly pointed to rounded-obtuse, are concave and sometimes cucullate. The variability of the costa, from one species to another and even from one leaf to another on the same plant, is a curious attribute ofthe genus. The capsules are short, broad, and not much curved, as in the Brachytheciaceae, but the yellow-brown peristome teeth, wet habitats, and commonly double costae are indicative of a relationship to the Amblystegiaceae.