TY - JOUR T1 - Phylogeny of Conradina and related southeastern scrub mints (Lamiaceae) based on GapC gene sequences JF - International Journal of Plant Sciences Y1 - 2008 DO - 10.1086/528758 A1 - Christine E Edwards A1 - David Lefkowitz A1 - Douglas E Soltis A1 - Pamela S Soltis SP - 579–594 KW - Accuracy KW - Congruence KW - Conradina KW - Dna-Sequences KW - Evolutionary Biology KW - Gapc KW - Incongruence KW - Inference KW - Lamiaceae KW - Length Difference Test KW - Nuclear Genes KW - Phylogeography KW - Recombination KW - Reconstruction KW - Species Phylogeny AB - Phylogeny reconstruction at the species level, especially using organellar markers, is often complicated by problems such as incomplete lineage sorting and interspecific hybridization. Single-copy nuclear genes may be useful for these cases because they have higher mutation rates and are biparentally inherited. One plant group in which hybridization and incomplete lineage sorting have been proposed based on analyses of internal transcribed spacer (ITS) and plastid data is a clade of mints from the southeastern United States: Conradina and the related genera Dicerandra, Piloblepbis, Stacbydeoma, and Clinopodium (Lamiaceae). To clarify the phylogeny in this clade and investigate the possibility of incomplete lineage sorting and interspecific hybridization, we isolated three members of the nuclear GapC gene family and used two to reconstruct phylogeny. Separate phylogenetic analyses of the two GapC loci did not resolve species relationships. We then used two approaches to concatenate the two heterozygous GapC loci with ITS and plastid data sets from a previous study and carried out combined analyses. Trees resulting from the two concatenation approaches were similar in the resolution and support of generic relationships, but they differed drastically in resolution and support for relationships within Conradina. Conradina species are probably very recently derived, and it may be unreasonable to reconstruct species relationships in Conradina using DNA sequence data due to widespread hybridization or lack of coalescence. Rapidly evolving microsatellite data may be more useful for detecting hybridization and clarifying species boundaries in Conradina. VL - 169 UR - http://www.journals.uchicago.edu/doi/abs/10.1086/528758 ER - TY - JOUR T1 - Using population genetic data as a tool to identify new species: Conradina cygniflora (Lamiaceae), a new, endangered species from Florida JF - Systematic Botany Y1 - 2009 A1 - Christine E Edwards A1 - Walter S Judd A1 - Gretchen M Ionta A1 - Brenda Herring SP - 1–13 AB - Understanding species limits in recent radiations is often difficult because sufficient time may not have elapsed since speciation to allow for the accumulation of unique species-specific traits. However, because population genetic markers evolve rapidly, patterns of genetic structure based on these markers can often discern genetically isolated population groups, even when other markers, such as DNA sequences, can not. In this study, we analyzed patterns of genetic structure based on microsatellites in Conradina and identified a group of plants in Dunns Creek State Park (Putnam County, Florida) that are genetically divergent from all other described Conradina species. We then carried out a mor- phological study that revealed several unique characters in these populations, most notably unicellular hairs, epidermis features, and larger calyces. Because these populations are genetically and morphologically diagnosable from all other Conradina species, we thus consider them to be specifically distinct, and name this taxon Conradina cygniflora. Conradina cygniflora is endemic to Dunns Creek State Park in south- central Putnam County, Florida, where it occupies eight tightly-clustered sites that probably form around two to four self-sustaining popula- tions. Due to its extremely limited geographic distribution and few individuals, we recommend that Conradina cygniflora be listed as federally endangered. VL - 34 ER -