Plants long and slender, to 10 cm long, 1.5-2 mm wide, pale green to yellowish-green, loosely creeping to laxly pendent. Stems with hyalodermis; ventral merophyte 2 cells wide. Leaf lobes spreading, apex narrow acuminate to broad rounded-apiculate, plane, margins entire or weakly crenulate; cells plane, with distinct trigones and intermediate thickenings; oil bodies small, finely granular; ocelli lacking. Lobules usually small, less than 1/3 leaf length, ovate, apical tooth short and blunt, hyaline papilla proximal. Underleaves bifid, large, 4-10x stem width, base often cordate, insertion line curved to deeply arched. Asexual reproduction not observed. Dioicous. Female branches very short, without innovations (rarely with 1 short lejeuneoid innovation). Perianths inflated, with 5 smooth keels or eplicate.