The Dicranaceae are a large family difficult to characterize because of internal variability and intergradations with nearby families. In general the plants are erect, the leaves narrow, the costa single and well-developed, the setae elongate, the capsules exserted, and the peristome teeth have a 2:3 haplolepideous pattern. Crum and Anderson (1981) noted that well-developed alar cells are generally associated with the family, but undifferentiated alar cells are commonly encountered, and both character states are found in some genera.
In Central America the genera can be clustered into four, weakly demarcated subfamilies. The Paraleucobryoideae are here synonymized with the Campylopodioideae. This decision is necessitated by the close gametophytic relationship of Paraleucobryum and Campylopus. Sporophytically only the well developed annulus of the Paraleucobryoideae separates the two. This character is of uncertain value in the Dicranaceae, due to its variable expression in the Anisothecioideae and the Dicranoideae.
The subfamilies and their genera, arranged systematically, are:
Anisothecioideae: Aongstroemia, Anisothecium, Dicranella, and Microcampylopus.
Campylopodioideae: Campylopodiella, Campylopus, Bryohumbertia, Dicranodontium, and Pilopogon.
Dicranoideae: Chorisodontium, Dicranum, Symblepharis, Holomitrium, Eucamptodontopsis, Schliephackea, Leucoloma, and Cynodontium.