Abbott, J. Richard , Neubig, K. M. .
Phylogeny of the Pawpaws (Asimina & Deeringothamnus, Annonaceae).
Commonly known as pawpaws and false pawpaws, Asimina and Deeringothamnus (Annonaceae) comprise ten species of shrubs to small trees, half of which are endemic to Florida, where three of them are rare, tracked species. Eight of the species are found in sandhill, flatwoods, and scrub vegetation, while two occur primarily in mesic forests. Results of phylogenetic analyses (using 13,755 base pairs from 11 chloroplast regions and 1 nuclear ribosomal DNA region) including all species of Asimina and Deeringothamnus will be discussed. Strongly supported conclusions are that 1) Deeringothamnus is phylogenetically nested within Asimina, 2) Asimina s.l. (including Deeringothamnus) is monophyletic, 3) Asimina triloba is sister to the remaining species, and 4) the New World Asimina clade is sister to the Old World group Disepalum. There is not complete congruence between traditional morphological views of the species and some of the genetic data, but it is not clear how much is due to retained ancestral polymorphisms versus hybridization. Hybridization has been reported for nearly all species, but some of the lateral gene flow is suspected to be historical, as the species are morphologically cohesive and distinctive. Asimina s.l. likely represents an old lineage with modern species being the result of a recent radiation, e.g., rapid morphological fixation without full genetic sorting.
Log in to add this item to your schedule
1 - Eastern Illinois University, Department of Biological Sciences, Charleston, IL, 61920, USA
2 - University of Florida, Florida Museum of Natural History, Gainesville, FL, 32611, USA
Presentation Type: Oral Paper:Papers for Sections
Location: 552A/Convention Center
Date: Tuesday, August 3rd, 2010
Time: 9:45 AM