Plants small to large, green, yellowish, or brownish. Stems distichously branched, sometimes almost unbranched; hyalodermis present or absent, cortical cells small, walls incrassate; paraphyllia present or absent; pseudoparaphyllia usually foliose, outer occasionally filamentous; rhizoids or rhizoid initials on stem at or just below leaf insertions or from proximal abaxial costa, occasionally from lamina near apex (Conardia), rhizoids red-brown, slightly or strongly branched, smooth or warty-papillose, rarely granular-papillose; axillary hairs usually well developed. Stem leaves straight, falcate, or squarrose, plicate or not; costa single, usually long, or double and usually short; alar cells differentiated or not, sometimes inflated; medial laminal cells linear or short-linear, rarely rectangular or hexagonal, 1-stratose or sometimes partially 2- or multistratose, smooth or rarely prorate or papillose. Perichaetia with inner leaves erect, straight, lanceolate, ovate, oblong, or slightly obovate, plicate or rarely not, margins entire or partly denticulate, apex usually acuminate, costa single or double, usually well developed, laminal cells usually smooth; paraphyses present. Seta long or rarely short, smooth. Capsule horizontal to erect, cylindric or short-cylindric, curved to straight; stomata with long pores; annulus separating or not; operculum conic, rarely rostrate or short-rostrate; peristome perfect or specialized; perfect exostomes yellow-brown or brownish, external surface cross striolate or sometimes reticulate proximally, papillose distally, margins dentate or slightly dentate, border ± widened at transitional zone in outer peristomial layer pattern; specialized exostome teeth variously narrow or short, external surface sometimes papillose basally; perfect endostome basal membrane high, segments long, not or narrowly perforate, cilia nodose or sometimes appendiculate; specialized endostome basal membrane ± reduced or sometimes absent, segments narrower, sometimes shorter than in perfect endostomes, cilia short to absent. Calyptra cucullate, smooth.
SELECTED REFERENCES Hedenas, L. and A. Vanderpoorten. 2006. The Amblystegiaceae and Calliergonaceae. In: A. E. Newton and R. S. Tangney, eds. 2006. Pleurocarpous Mosses: Systematics and Evolution. Boca Raton. Pp. 163-176. Ochyra, R. 1989. Animadversions on the moss genus Cratoneuron (Sull.) Spruce. J. Hattori Bot. Lab. 67: 203-242. Vanderpoorten, A. et al. 2002. Phylogeny and morphological evolution of the Amblystegiaceae (Bryopsida). Molec. Phylogenet. Evol. 23: 1-21. Vanderpoorten, A. et al. 2002b. Circumscription, classification, and taxonomy of Amblystegiaceae (Bryopsida) inferred from nuclear and chloroplast DNA sequence data and morphology. Taxon 51: 115-122. Vanderpoorten, A., A. J. Shaw, and B. Goffinet. 2001. Testing controversial alignments in Amblystegium and related genera. (Amblystegiaceae: Bryopsida). Evidence from rDNA ITS Sequences. Syst. Bot. 26: 470-479.