Some other families are recognised by other sources:
Ephemeraceae – this putative family is characterized by highly simplified vegetative and sporogenous bodies and contains two genera, Ephemerum and Micromitrium. However, phylogenetic analysis finds it polyphyletic, with Ephemerum nested in Pottiaceae and Micromitrium recovered among the Dicranales, closely related to the Leucobryaceae, and assigned a new family, Micromitriaceae.