Phylogeny and colonization history of Pringlea antiscorbutica (Brassicaceae), an emblematic endemic from the South Indian Ocean Province

• Published in: Molecular Phylogenetics and Evolution
• Main Authors: Bartish, Igor V., Ainouche, A., Jia, D. (Dongrui), Bergstrom, D., Chown, S.L., Winkworth, R.C., Hennion, F.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2012
• Subjects: biogeography; long-distance dispersal; molecular dating; Antarctic; Indian; Antarc*
• Online Access: https://doi.org/10.1016/j.ympev.2012.07.023; http://hdl.handle.net/11104/0211845

The origins and evolution of sub-Antarctic island floras are not well understood. In particular there is uncertainty about the ages of the contemporary floras and the ultimate origins of the lineages they contain. Pringlea R. Br. (Brassicaceae) is a monotypic genus endemic to four sub-Antarctic island groups in the southern Indian Ocean. Our phylogenetic analyses confirm that Pringlea falls within the tribe Thelypodieae. Divergence time estimates and ancestral area reconstructions imply Pringlea diverged from a South American ancestor 5 Myr ago. We found that several long-distance dispersal events must be inferred to explain the current distribution of this species. Although Pringlea is likely to have inherited cold tolerance from its closest relatives, the distinctive morphology of this species likely evolved only after it split from the South American lineage. Our results lend support to the hypothesis that angiosperms persisted on the sub-Antarctic islands throughout the ice ages.