A molecular estimate of the phylogeny of Styphelieae (Ericaceae)

Abstract

Parsimony analyses of sequence data derived from two regions of the chloroplast genome, matK and the atpB-rbcL intergenic spacer, separately and together, are reported for Styphelieae. Taxonomic sampling includes representatives of all currently accepted genera apart from the two non-Australian monotypics, Cyathopsis Brongn. & Gris and Decatoca F.Muell., and of all subgenera or informal infrageneric groups except for Trochocarpa subgenus Pseudocyathodes Sleumer. A well resolved estimate of the phylogeny of the tribe is obtained, with high levels of jackknife support for terminal groupings. The results provide support for the current concepts of Acrotriche R.Br., Androstoma Hook.f., Croninia J.M.Powell, Cyathodes Labill. sensu Weiller, Leptecophylla C.M.Weiller, Leucopogon R.Br. sensu Taaffe et al., Pentachondra R.Br., Planocarpa C.M.Weiller and Trochocarpa R.Br., but the following genera appear paraphyletic: Astroloma R.Br., Brachyloma Sond., Cyathodes sensu Labill., Leucopogon R.Br. sensu lato, Lissanthe R.Br., Monotoca R.Br. and Styphelia Sm. (sensu Bentham). Several robust clades are identified as potential new genera but formalisation of nomenclatural changes is left, pending morphological analyses of the various clades to identify synapomorphies with which to characterise generic groupings. The general approach to be adopted in this endeavour is discussed, with narrower generic concepts being favoured as more informative and less disruptive of the existing nomenclature.