Abstract Detail

Systematics Section/ASPT

Grissom, Joseph [1], Hufford, Larry [2].

Phylogeny of Mentzelia section Mentzelia (Loasaceae): Implications for Taxonomy and Biogeography.

Mentzelia section Mentzelia (Loasaceae), which currently consists of approximately 25 species, is distributed widely in arid regions of North, Central, and South America, although it is also found in the Caribbean and Florida. We used phylogeny reconstruction to assess the taxonomy and to test hypotheses of biogeographic change in the group. Our molecular phylogenetic approach used sequence data from nrITS and the plastid matK, rps16-trnk, trnL-F, and ndhf-rpl32 regions to reconstruct relationships. Our results indicated M. arborescens was more closely related to a clade consisting of Mentzelia sections Bartonia, Bicuspidaria, and Trachyphytum than to section Mentzelia. In section Mentzelia, M. adhaerens was sister to the remainder of the section. We recovered support for M. pachyrhiza + M. parvifolia as sister to M. pattersonii + M. oligosperma. Mentzelia floridana, found in the Caribbean and Florida, was recovered as sister to the Mexican M. hispida. Relationships of the South American M. scabra, M. sericea, and M. angurate were equivocal. Mentzelia lindheimeri was discovered to be paraphyletic to M. hispida, M. gypsophila, and M. asperula. Phylogenetic results and morphological characters supported the resurrection of M. gracilis as a species separate from M. hispida and its placement as sister to M. floridana. Our geographic reconstructions indicated that section Mentzelia originated in the northern portion of its range and expanded eastward into the Caribbean and Florida and southward into South America. Taxa found in South America were not monophyletic, and we inferred multiple southward migrations into South America. The geographically widespread M. aspera and M. oligosperma were both well supported as monophyletic.

Broader Impacts:

1 - Washington State University, School of Biological Science, 312 Abelson Hall, Pullman, WA, 99164, United States
2 - Washington State University, SCHOOL OF BIOLOGICAL SCIENCES, 312 Abelson Hall, PULLMAN, WA, 99164-4236, USA

Keywords:
Loasaceae
Mentzelia
ancestral area reconstruction
Taxonomy
biogeography.

Presentation Type: Oral Paper:Papers for Sections
Session: 4
Location: Magnolia/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 9:30 AM
Number: 4005
Abstract ID:722
Candidate for Awards:None