A revision of the Australian species of Parahebe and Derwentia (Scrophulariaceae)

A revision of the Australian species of Parahebe and Derwentia (Scrophulariaceae). Telopea 5 (1): 241-287. The relationships of the Australian species placed in or related to Parahebe W. Oliver are considered. It is concluded, on the basis of phylogenetic analyses to be published elsewhere, that only one Australian species is appropriately referred to Parahebe, nam ely P. lithophila, which is described as a new species. The genus Derwentia Raf. is revived for a group of eight species restricted to Australia and previously undescribed or referred to Veronica or Parahebe. D erw entia arcuata, D . b lak elyi and D . velutina are described as new. Combina tions are provided for D . arenaria and D . nivea, both transferred from Veronica, as w ell as for D . derw entiana (including five subspecies). The chromosome number n=21 is reported for Parahebe lithophila and n=20 and 19 in Derwentia. The Tasmanian Veronica formosa is discussed and is considered