Abstract Detail

Systematics Section

Berger, Brent A. [1], Sytsma, Kenneth J. [2].

The Myrtales: Dating, Character Evolution and a New Family?

The order Myrtales is a charismatic group of plants traditionally united by the presence of intraxylary phloem and vestured pits. Recent molecular work at both the ordinal and familial levels supports the inclusion of 9 families within the order: Alzateaceae, Combretaceae, Crypteroniaceae, Lythraceae, Melastomataceae (incl. Memecylaceae), Myrtaceae (incl. Heteropyxidaceae and Psiloxylaceae), Onagraceae, Penaeaceae (incl. Oliniaceae and Rhynchocalycaceae) and Vochysiaceae. Previous molecular studies resolve most interfamilial relationships, with the exception being the placement of the Combretaceae. The latter family has been suggested to be either sister to the Onagraceae + Lythraceae subclade or as sister to all families in the order. Resolving the placement of Combretaceae is important both in terms of temporally dating geographical events in the order and in elucidating morphological and anatomical evolution in the order. Our study incorporates molecular data from 6 genes spanning all three genomes, as well as morphological data, to confidently place the Combretaceae in a clade with the Onagraceae + Lythraceae, which is then sister to the rest of the order. Using the well-resolved phylogeny, we explore the following: 1) the date of the crown node of the Myrtales and major radiations within the order, 2) the evolutionary patterns of several characters across the order, and 3) the taxonomic implications related to the placement of the genus Strephonema (Combretaceae).

Broader Impacts:

1 - University of Wisconsin-Madison, Department of Botany, Birge Hall, 430 Lincoln Drive, Madison, WI, 53706-1381, USA
2 - University of Wisconsin Madison, Department of Botany, Birge Hall, 430 Lincoln Drive, Madison, Wisconsin, 53706-1381, USA

Keywords:
Myrtales
Combretaceae
Strephonema
character evolution
Dating
phylogeny.

Presentation Type: Oral Paper:Papers for Sections
Session: 56
Location: 556B/Convention Center
Date: Wednesday, August 4th, 2010
Time: 3:45 PM
Number: 56011
Abstract ID:258