title: Resolving phylogenetic relationships of the recently radiated carnivorous plant genus Sarracenia using target enrichment.
abstract: The North American carnivorous pitcher plant genus Sarracenia (Sarraceniaceae) is a relatively young clade (<3 million years ago) displaying a wide range of morphological diversity in complex trapping structures. This recently radiated group is a promising system to examine the structural evolution and diversification of carnivorous plants; however, little is known regarding evolutionary relationships within the genus. Previous attempts at resolving the phylogeny have been unsuccessful, most likely due to few parsimony-informative sites compounded by incomplete lineage sorting. Here, we applied a target enrichment approach using multiple accessions to assess the relationships of Sarracenia species. This resulted in 199 nuclear genes from 75 accessions covering the putative 8-11 species and 8 subspecies/varieties. In addition, we recovered 42kb of plastome sequence from each accession to estimate a cpDNA-derived phylogeny. Unsurprisingly, the cpDNA had few parsimony-informative sites (0.5%) and provided little information on species relationships. In contrast, use of the targeted nuclear loci in concatenation and coalescent frameworks elucidated many relationships within Sarracenia even with high heterogeneity among gene trees. Results were largely consistent for both concatenation and coalescent approaches. The only major disagreement was with the placement of the purpurea complex. Moreover, results suggest an Appalachian massif biogeographic origin of the genus. Overall, this study highlights the utility of target enrichment using multiple accessions to resolve relationships in recently radiated taxa.
authors.affiliation: Department of Plant Biology, University of Georgia, Athens, GA 30602, United States. Electronic address: jstephens@plantbio.uga.edu.
authors.forename: Jessica D
authors.initials: JD
authors.lastname: Stephens
authors.affiliation: Department of Plant Biology, University of Georgia, Athens, GA 30602, United States. Electronic address: bonjour@uga.edu.
authors.forename: Willie L
authors.initials: WL
authors.lastname: Rogers
authors.affiliation: Department of Plant Biology, University of Georgia, Athens, GA 30602, United States. Electronic address: kheyduk@plantbio.uga.edu.
authors.forename: Karolina
authors.initials: K
authors.lastname: Heyduk
authors.affiliation: Atlanta Botanical Garden, 1345 Piedmont Ave NE, Atlanta, GA 30309, United States. Electronic address: JSanders@atlantabotanicalgarden.org.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Cruse-Sanders
authors.affiliation: Atlanta Botanical Garden, 1345 Piedmont Ave NE, Atlanta, GA 30309, United States. Electronic address: rdetermann@atlantabotanicalgarden.org.
authors.forename: Ron O
authors.initials: RO
authors.lastname: Determann
authors.affiliation: Department of Environmental Health Science, University of Georgia, Athens, GA 30602, United States. Electronic address: travisg@uga.edu.
authors.forename: Travis C
authors.initials: TC
authors.lastname: Glenn
authors.affiliation: Department of Plant Biology, University of Georgia, Athens, GA 30602, United States. Electronic address: russell@plantbio.uga.edu.
authors.forename: Russell L
authors.initials: RL
authors.lastname: Malmberg
mesh_terms: D005075:Biological Evolution; D002467:Cell Nucleus / Q000235:genetics; D018742:DNA, Chloroplast / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D016013:Likelihood Functions; D008957:Models, Genetic; D010802:Phylogeny; D052583:Sarraceniaceae / Q000145:classification*; D017422:Sequence Analysis, DNA
chemical_list: D018742:DNA, Chloroplast; D018744:DNA, Plant
keywords: Coalescent; Gene capture; Phylogenomics; Pitcher plants; Species tree estimation