Abstract Detail

Systematics

Barrett, Craig [1], Sinn, Brandon [2], King, Loren [1], medina, jesus [3], Bacon, Christine [4], Hodel, Donald [5], lahmeyer, sean [6].

Phylogenomics, biogeography, and evolution in the American palm genus Brahea Mart. Ex Endl.

Slow rates of molecular evolution at low taxonomic levels hamper studies of relationships among species, and subsequent biogeographic and evolutionary analyses. A prime example is the genus Brahea Mart. Ex Endl., which is among the most poorly understood groups of American palms, furthermore displaying a variety of growth forms and intermediate morphological characteristics. Currently, no explicit phylogenetic hypothesis exists for the genus. We generated approximately 400 kb of genome-scale data from all three genomes to resolve and provide support for relationships among the 12 or so currently described species of Brahea. Relationships were strongly supported, and conform to previous subgeneric circumscriptions, except for placement of the dwarf species B. moorei within subgenus Brahea. We were able to reconstruct ancestral ranges to varying degrees among the three major clades of Brahea, but ancestral ranges at the deepest nodes were equivocal. Reconstruction of ancestral growth form (i.e. plant height) elucidated trends including an overall increase in height in the B. armata clade, and independent evolution of dwarf forms from taller ancestors in the B. pimo and B. dulcis clades. We found evidence of niche non-equivalency among species within the B. armata clade in northwestern Mexico, and some limited evidence of differentiation between B. berlandieri and B. dulcis, the former of which are currently synonymized under B. dulcis. Our findings have implications for the complex biogeographic history in Central America and Mexico, and advance our understanding of patterns of biodiversity in these ecologically and economically important palms.

1 - West Virginia University, Biology, 53 campus dr, Morgantown, WV, 26506, US
2 - West Virginia University, Biology, Life Sciences Building, 53 Campus Drive, Morgantown, WV, 26506, United States
3 - California State University, Los Angeles, Biological Sciences
4 - University of Gothebburg, Gothenburg Global Biodiversity Centre, Box 461, SE 405-30, Göteborg, Sweden
5 - University of California Cooperative Extension, 700 West Main Street, Alhambra, California , 91801, USA
6 - The Huntington Library, Art Collections, and Botanical Gardens, Herbarium, 1151 Oxford Road, San Marino, California, 91801, US

Keywords:
Arecaceae
Phylogenetics
genome skimming
Next generation sequencing
plastome
growth form
ecological niche model.

Presentation Type: Oral Paper
Session: 3, Systematics I--Tracheophytes, Pteridophytes to Monocots 1
Location: 110/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 8:45 AM
Number: 3004
Abstract ID:276
Candidate for Awards:None