This paper provides a taxonomic revision of the Australasian genera Dracophyllum and Richea. The former genus is revised with a total of 61 species being recognised in four subgenera and two species are listed as incertae sedis. The latter genus is reduced to synonymy under Dracophyllum where it is divided into two new subgenera, Cystanthe and Richea. The 61 taxa occur mostly in New Zealand (35 taxa) with smaller numbers in Australia (18 taxa) and New Caledonia (8 taxa), all endemic to their respective countries. Replacement names and new combinations are published in this paper, and nomenclature, descriptions, illustrations, photographs and distribution maps are provided for each species, along with designated lectotypes, where necessary, and a key to the subgenera and keys to species within these are provided.

Amplicon sequencing of plastid and nuclear DNA showed phylogeographic structure in Xanthorrhoea, despite extremely low genetic variation and widespread sharing of identical DNA sequence among multiple species (sometimes across significant geographic distance). Plastid loci identified three geographic groups, South West + Central Australia, North East Australia, and South East Australia, indicating restricted gene flow among regions. nrDNA sequence showed less variation, with one haplotype being widespread, found in all three plastid geographic groups and 70% of species, and a pattern suggesting at least two east–west divergences.