Abstract Detail



Systematics

Roy, Tilottama [1].

Investigating evolutionary relationships within Pogostemoneae and Gomphostemmateae (Subfamily:Lamioideae; Family:Lamiaceae).

The family Lamiaceae is one of the most species-rich angiosperm families, characterized by a suite of morphological characters. Lamiaceae is divided into seven subfamilies, of which Lamioideae is the second largest and exhibits a remarkable diversity of morphology and habitat. Lamioideae is further subdivided into ten tribes, of which Gomphostemmateae and Pogostemoneae are predominantly Old World, with many of their members being extensively used in medicinal and cultural purposes. Our previous study utilizing chloroplast (cpDNA) and the low copy nuclear-encoded DNA locus PPR showed cytonuclear discordance, placing members of each of these two tribes into two distinctly well supported clades in the nuclear phylogeny, whereas the cpDNA phylogeny still resolved each tribe as monophyletic. However, even the cpDNA tree showed these two tribes comprising of two separate subclades, with taxa in each clade showing morphological similarities with each other, but substantially differing from members of the other clade. Introns from low-copy nuclear markers provide high variability due to a higher rate of nucleotide substitutions and are thus phylogenetically more informative among closely related taxa. This has led us to pursue further research incorporating three more independently inherited low copy nuclear loci (COR, NIA and ADH), with a variety of phylogenetic methods, as well as an extended sampling with more representative taxa from each clade within these two tribes, to delve further into their taxonomic positions and clarifying phylogenetic affinities within these two tribes as well as their possible re-circumscription.


1 - Missouri Western State University, Biology, 4525 Downs Drive, Saint Joseph, MO, 65407, USA

Keywords:
Lamiaceae
Gomphostemmateae
Pogostemoneae
Evolutionary relationships
cpDNA
nuclear loci
phylogenetic affinities.

Presentation Type: Oral Paper
Number:
Abstract ID:134
Candidate for Awards:None


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