A phylogenetic recircumscription of Styphelia (Ericaceae, Epacridoideae, Styphelieae)

Abstract

The taxonomic limits of Styphelia (Ericaceae, Epacridoideae, Styphelieae) have been contentious since the genus was first described. At one extreme, it has been circumscribed so broadly as to include most epacrids with drupaceous fruit, at the other, to include only those species that also have long-exserted anthers and styles. Recent molecular phylogenetic analyses have indicated that while all previous circumscriptions of Styphelia are non-monophyletic, a large clade (the Astroloma–Styphelia clade) is consistently well supported. This clade comprises Astroloma, in part (i.e. section Stomarrhena sensu Bentham), Coleanthera, Croninia, Leucopogon, in part (i.e. section Pleuranthus sensu Bentham) and Styphelia sensu Bentham. On the basis of those analyses, we here recircumscribe Styphelia phylogenetically to include all species belonging to the Styphelia–Astroloma clade. The 146 taxa occur mostly in Australia, with smaller numbers in New Zealand, New Caledonia (1 species extends to Fiji and Vanuatu) and Malesia. An additional 74 phrase-named taxa belong to this clade, including 70 from Western Australia and 4 from eastern Australia (all other Australian states and territories). The Styphelia floras of Western Australia, eastern Australia, New Caledonia and Malesia are each endemic or nearly so; 1 species (S. nesophila (DC.) Sleumer) is shared between New Zealand and eastern Australia, and 2 species (S. cordifolia (Lindl.) F.Muell. and S. woodsii (F.Muell.) F.Muell.) are shared between Western Australia and eastern Australia. An amended diagnosis of Styphelia is provided, new combinations are made for 25 taxa, and new names published for another 9. Lectotypes are designated for two names (Leucopogon brevicuspis Benth. and L. strictus Benth.) found to have taxonomically heterogeneous syntypes.