A phylogenetic analysis of the Eucryphiaceae

Abstract

A range of characters from modern and fossil species are used to present a phylogeny of Eucryphia Cav. (Eucryphiaceae). Amongst the extant taxa, the Australian species form a monophyletic group, but the South American species are paraphyletic. This, coupled with their present-day distribution and the fossil record, supports the view that Eucryphia had a Gondwanic origin at least 50 million years prior to the disruption of Australia from Antarctica. Although based on a limited data set with only vegetative characters available, the inclusion of the fossil members of Eucryphiaceae has demonstrated several trends that have been inferred to represent a response to the changing climatic conditions of the Cenozoic. These responses have included a general decrease in leaf size, loss of serrate leaf margins and the development of peltiform cuticular extensions on the abaxial leaf surface. These extensions may aid in decreasing transpirational water loss and/or increasing frost resistance.