Abstract Detail

Systematics

Vignovich, William [1], Stonehouse, Gavin [1], Wood, Kenneth [2], Abbott, J. Richard [3], Naczi, Robert [3], Majure, Lucas [4], Neubig, Kurt Maximillian [1].

The origin and diversification of Dichanthelium (Poaceae) in Hawaii.

The genus Dichanthelium is a phylogenetically poorly resolved taxon originally treated as a subgenus of Panicum (Poaceae). Dichanthelium is most diverse in eastern North America; however, the group is also widespread in tropical areas in Central and South America, as well as in the Hawaiian Islands. The purpose of this research was to study the biogeographic distribution of the Hawaiian representatives of this genus, because this represents a very unusual biogeographic pattern, as the only representatives of the genus outside of the Americas. The secondary objective was to understand patterns of speciation within the Hawaiian species. We used 3 DNA regions (GBSSI, nrITS, and rpl32-trnL) to develop a phylogenetic hypothesis of relationships in the genus for both Hawaiian and North American species. These results indicate that the Hawaiian species form a clade and that they most likely arrived via dispersal from a North American ancestor. Of the 4 Hawaiian species, D. hillebrandianum is likely a species of hybrid origin, originating from the largely sympatric Hawaiian species D. cynodon and D. isachnoides. By determining the interrelationship of evolutionary processes and geographic distribution, we can achieve a better understanding of patterns of diversification in the landscape.

1 - Southern Illinois University Carbondale, Plant Biology, Carbondale, IL, 62901, USA
2 - National Tropical Botanical Garden, 3530 Papalina Road, Kalaheo, HI, 96741, USA
3 - The New York Botanical Garden, Bronx, NY, 10458, USA
4 - Desert Botanical Garden, Department of Research, Conservation, and Collections, Phoenix, AZ, 85008, USA

Keywords:
Hawaii
Interspecific hybridization
phylogenetics.

Presentation Type: Poster
Session: P, Systematics Section/ASPT Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PSY019
Abstract ID:117
Candidate for Awards:None