Abstract Detail

Systematics

Whitley, Breanna [1], Neubig, Kurt [2], Garwood, Nancy [3].

Disentangling the lineages of Trema micrantha using phylogenetics and biogeography .

Species circumscriptions in Trema, a pantropical genus of pioneer trees in Cannabaceae, have long been variable and inaccurate. The Neotropical species of Trema contain a considerable amount of this variability, specifically in the polyphyletic and widely distributed Trema micrantha. In this study, we sought to analyze the phylogenetic relationships and geographic distributions within Trema to more accurately reflect species diversity. We sampled five gene regions including ETS, ITS, rbcL, trnH-psbA, and trnL-F to resolve relationships within T. micrantha across it’s geographic and morphological range. We found three clades (designated as clades A, B, & C), ranging from Florida to Argentina. Clade A is differentiated by brown endocarps. Clade B is differentiated by black endocarps. And clade C is differentiated by a montane distribution. Clades A and C are well supported phylogenetically with well-defined morphological differences and deserve recognition as distinct species. However, in clade B, two extremely morphologically diverse subclades (B1 & B2) were identified. Although these subclades have significant overlap in Central America, our study indicates that B2 is more widely distributed throughout South America and the Caribbean while B1 is more restricted to Central America. We will use these results to guide decisions of species circumscription in a taxonomic revision of Trema.

1 - Southern Illinois University, Department Of Plant Biology, 1125 Lincoln Dr., LSII, Room 420, Carbondale , IL, 62901, United States
2 - Southern Illinois University, Dept Of Plant Biology, 1125 Lincoln Dr., Life Science II, Room 420, Carbondale, IL, 62901, United States
3 - Southern Illinois University, Plant Biology, 1125 Lincoln Ave., Life Science II, Mailcode 6509, Carbondale, IL, 62901, United States

Keywords:
Phylogenetics
Biogeography
Systematics 
Taxonomy.

Presentation Type: Poster
Session: P, Systematics
Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 5:30 PM This poster will be presented at 6:15 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: PSY008
Abstract ID:882
Candidate for Awards:None