Abstract Detail

Systematics Section

Samarakoon, Tharangamala [1], Dement, Angela [2], Alford, Mac [2].

Phylogeny, character evolution, and classification of the tropical angiosperm family Samydaceae (Malpighiales).

The flowering plant family Samydaceae was recently circumscribed to include 14 genera and about 240 species of tropical trees and shrubs. Preliminary analyses of relationships in the family, however, indicated that the largest genus, Casearia, is not monophyletic and that several smaller groups are probably misplaced. In order to affirm or refute those hypotheses, additional morphological and DNA sequence data were gathered for analysis. In particular, rapidly evolving plastid and nuclear DNA regions were sampled for characters. The results continue to indicate, now with more support, that Casearia is not monophyletic. Rather, several small genera are nested within a broader Casearia, namely Samyda, Laetia, Hecatostemon, and Zuelania. The results suggest that one previously recognized genus, Piparea, should be reinstated and that a new genus should be created for Laetia sect. Scypholaetia, which is closely related to Piparea, Ryania, and Trichostephanus. Unfortunately, because the name Laetia predates Casearia, a conservation proposal must be introduced in order to maintain the name Casearia for the majority of the species currently recognized as Casearia.

Broader Impacts:
Angela D. Dement was able to work on this project because of an NSF grant to the University of Southern Mississippi for enhancing minority research and preparation for graduate school (AGEM=Alliance for Graduate Education in Mississippi). She is now planning for graduate school in genetics/bioinformatics.

1 - University of Southern Mississippi, Department of Biological Sciences, 118 College Drive #5018, Hattiesburg, MS, 39406, U.S.A.
2 - University of Southern Mississippi, Department of Biological Sciences, 118 College Drive #5018, Hattiesburg, MS, 39406, USA

Keywords:
Samydaceae
Flacourtiaceae
Salicaceae sensu lato
Malpighiales
Casearia.

Presentation Type: Oral Paper:Papers for Sections
Session: 9
Location: Ballroom B/Convention Center
Date: Monday, August 2nd, 2010
Time: 2:00 PM
Number: 9005
Abstract ID:510