Trachyphyllum is transferred from the Entodontaceae to the Thuidiaceae on the basis of correlated gametophytic and sporophytic characters.
The genus is considered to consist of two subgenera: subg.
Trachyphyllum for
T. inflexum (with numerous new synonyms),
T. gastrodes, T. dusenii and
T. borgenii; and subg.
Carinatum, subg. nov., for
T. carinatum,
T. jeyporense and
T. touwianum, n. sp. All the species are keyed, described and illustrated.