The austral biogeographic pattern refers to the presence of congeneric organisms in South America, Australasia and/or Africa and is generally considered to be a classic vicariant scenario associated with the breakup of Gondwana. Results from phylogenetic studies and fossil record evidence of Nothofagus and Araucaria, both woody forest genera, are congruent with this hypothesis. However, the same history may not apply to all genera in austral areas. It has been hypothesized that higher elevation herbaceous taxa may be of more recent origin, suggesting that long-distance dispersal may have played a role in their historical biogeography. An extensive phylogenetic study of austral, subalpine Ourisia (Veronicaceae/ Scrophulariaceae s.l.) based on molecular and morphological data is currently underway to investigate the biogeography and evolution within the genus. The approximately 30 species of Ourisia are distributed equally between the South American Andes (Venezuela to Tierra del Fuego) and the New Zealand Southern Alps. One species is also endemic to high-elevation habitats in Tasmania, Australia. Historically, Ourisia has been divided into two subgenera (each with a bihemispheric distribution) based on calyx symmetry and corolla tube curvature. Our current data sets include the nuclear Internal Transcribed Spacer (ITS1, 5.8S, ITS2) and chloroplast matK-3trnK sequences for 22 species and subspecific entities of Ourisia. The inferred phylogenies from both separate and combined data sets show that: 1) Ourisia is monophyletic, 2) the subgenera as currently circumscribed are not monophyletic, 3) three suffruticose Andean taxa are sister to the rest of Ourisia, and 4) the New Zealand taxa form a monophyletic clade embedded within the Andean Ourisia. These findings suggest that it is highly unlikely that a vicariant event is responsible for the current biogeography of the genus, and instead long-distance dispersal from South America to New Zealand is a more plausible explanation.

Key words: Andes, biogeography, New Zealand, Ourisia, Scrophulariaceae, Tasmania