Rhabdoweisiaceae Limpr.

Plants small to medium-sized, occasionally robust. Stems erect, mostly lacking a central strand (but present in Dicranoweisia), with firm-walled cortical cells. Leaves mostly lanceolate, often strongly contorted when dry. Upper laminal cells short, often with some oblate, smooth or papillose, sometimes bearing longitudinal cuticular striations that extend over the cell walls (present in all N.Z. taxa).

Autoicous. Perigonia often on short branches at the base of the perichaetia. Setae elongate or short; capsules mostly erect, symmetric, and short-cylindric to ellipsoid, less often asymmetric, sometimes furrowed when dry; operculum rostrate. Peristome single or sometimes absent, with 16 teeth mostly undivided, variously ornamented. Calyptra cucullate, smooth.

There is little consensus concerning the size or the limits of this morphologically diverse family. The brief description above is derived primarily from the type genus and the genera occurring in N.Z. The type genus, the predominantly northern hemisphere Rhabdoweisia, was placed (with Amphidium) in a subfamily Rhabdoweisioideae within the Dicranaceae by Brotherus (1924). Modern Floras have either recognised that subfamily at the family rank (Smith 2004) or subsumed it within the larger Dicranaceae (e.g., Crum & Anderson 1981; Ireland et al. 1994). While retaining it in the Dicranales, Goffinet et al. (2009) presented a much expanded interpretation of the family, which is largely adopted here. Only three of the 15 genera they include in the family occur in N.Z. (They also included Kiaeria in the Rhabdoweisiaceae, but that genus is retained here in the Dicranaceae.)