Article ID Journal Published Year Pages File Type
5919316 Molecular Phylogenetics and Evolution 2014 10 Pages PDF
Abstract

•We test the monophyly of an Australian endemic plant genus, Logania.•We test biogeographic hypotheses to explain the disjunct distribution of Logania.•Logania is polyphyletic; its two constituent sections represent separate genera.•Dispersal is the probable cause for the disjunct distribution of L. sect. Logania.•Vicariance may be responsible for the disjunct distribution of L. sect. Stomandra.

The angiosperm genus Logania R.Br. (Loganiaceae) is endemic to the mainland of Australia. A recent genetic study challenged the monophyly of Logania, suggesting that its two sections, Logania sect. Logania and Logania sect. Stomandra, do not group together. Additionally, the genus has a disjunct distribution, with a gap at the Nullarbor Plain in southern Australia. Therefore, Logania is a favourable candidate to gain insight into phylogenetic relationships and how these might intersect with Earth-history events. Our phylogenetic analyses of DNA sequences of two chloroplast markers (petD and rps16) showed that Logania sect. Logania and L. sect. Stomandra were each resolved as monophyletic, but the genus (as currently circumscribed) was not. Based on our Bayesian estimates of divergence times, the disjunct distributions within Logania sect. Stomandra could have been caused by flooding of the Eucla Basin. However, this biogeographical process cannot account for the distribution of Logania sect. Logania, with long-distance dispersal and establishment seeming more likely.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide

Related Topics
Life Sciences Agricultural and Biological Sciences Ecology, Evolution, Behavior and Systematics