DISSERTATION RESEARCH: Systematics and Biogeography of the tribe Vanilleae (Orchidaceae), and a monograph of the genus Epistephium

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

The orchid family may be the largest family of flowering plants, with dozens of new species being described each year, mostly from the tropics. This research will contribute to be a better understanding of the orchid family by focusing on the poorly known neotropical genus, Epistephium. Researchers will first reconstruct phylogenetic relationships within the genus, and then use the resulting phylogeny to conduct a species-level systematic revision. One graduate student and several undergraduates will be trained in systematic revisionary studies and molecular phylogenetics. International research infrastructure will be enhanced through collaborations with researchers in Ecuador and Brazil. The research also offers to provide new insights into evolutionary relationships within the Vanilloideae subfamily, that contains the economically important genus, Vanilla. This project aims to fully resolve the phylogenetic relationships of the tribe Vanillieae, which encompasses most tropical representatives of the subfamily Vanilloideae. Researchers will employ next-generation sequencing approaches to collect large amounts of DNA sequence data from all genera in the tribe and facilitate reconstruction of a highly supported phylogenetic tree. The resulting phylogenetic hypothesis will in turn allow a deeper analysis of the current and historical biogeographic distribution of the tribe (involving two examples of trans-Atlantic disjunctions and the opportunity to study island biogeography in the Pacific and SE Asia). Phylogenetic tests for vicariance and long distance dispersal will then be conducted out to identify how the group attained its current distribution. Lastly, a species-level monograph of Epistephium, the second largest genus in the tribe, will be produced.