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Land use changes by humans have eliminated more than half of the wetlands in Florida over the last 200 years, and additional losses are anticipated as a consequence of climate change and ongoing development activities that will accommodate a rapidly growing human population. Both spell danger for the biodiversity and ecosystem services in Florida, and data are needed to inform conservation priorities and actions concerning threatened or endangered wetland species. We modeled the projected distribution of an endangered epiphyte native to the forested wetlands in South Florida, Guzmania monostachia (Bromeliaceae), in response to changing climate and sea level conditions. We constructed ecological niche models (ENMs) under the present framework by using georeferenced occurrence points and projected them into the past and future under different scenarios. Our future climate-based ENMs predicted small losses in suitable habitat for G. monostachia in South Florida, with expansions into higher latitudes due to the warmer climate. In contrast, the models predicted a considerable, although non-detrimental, loss of suitable habitat due to rising sea levels. The combined results suggest that human activity is and will remain the largest threat to G. monostachia in Florida, and conservation efforts should focus on preserving existing habitats that will remain above sea level and explore possibilities for assisted migration.

International audience; The genus Berthelotia DC. (presently a synonym of the accepted name Pluchea Cass.), Asteraceae, Inuleae has been regarded as comprising two species, B. lanceolata DC. and B. sericea (Nutt.) Rydb. It honors the French naturalist Sabin Berthelot (1794-1880) for his contribution to the studies of the flora and fauna of the Canary Islands. Under the leadership of Philip B. Webb (1793-1854), Berthelot co-authored the most important work pertinent to the natural history of this archipelago: Histoire Naturelle des Îles Canaries. The nomenclature of Berthelotia and its associated names are revisited here. The holotype of Polypappus sericeus Nutt. (K000974653) was located, and lectotypes were assigned to B. lanceolata (G00450458) and B. lanceolata var. senegalensis DC. (G00452584). Phylogenetic analyses based on nucleotide sequences of the nrDNA ITS were conducted focusing on members of what is known as the Clade J of the Inuleae. A well-supported clade (100% P.P.) that we have labeled as "Clade I" was uncovered, and it is composed of three species that belong to the Pluchea indica Clade plus P. dioscoridis and P. ovalis; but this lineage did not support a previous hypothesis to include P. lanceolata. The two species of Berthelotia did not form a monophyletic group and seem to be distantly related; furthermore, none of these two taxa is sister to 208 Andre A. Naranjo et al. Tessaria, a South American genus that has been suggested to be a close relative to Berthelotia. Ethnobotanical uses of B. lanceolata and B. sericea are reviewed.

Understanding patterns of speciation and subsequent gene flow can clarify the evolutionary origins and history of species endemic to a specific geographic region and reveal genetic patterns important for conservation and management of rare species. We chose Dicerandra from the North American Coastal Plain biodiversity hotspot as a model to explore these concepts because of its endemism and the threatened status of most of its species. Using microsatellite-based population-level analyses of 32 populations from four of the annual species (D. linearifolia var. linearifolia, D. linearifolia var. robustior, D. fumella, D. odoratissima, and D. radfordiana), we addressed questions of genetic diversity, population structure, and hybridization. Strong support was found for the species-level recognition of the recently described D. fumella from the Florida panhandle. Dicerandra linearifolia var. linearifolia showed some regional cohesion of populations, but there was no consistent geographic pattern to the clustering of populations. Dicerandra radfordiana showed consistent clustering with proximate populations of D. odoratissima. Given that D. radfordiana is found at the southeastern extreme of the range of D. odoratissima, these populations may represent the early stages of speciation by isolation. While there are morphological and bioclimatic niche distinctions between D. odoratissima and D. radfordiana, there is no molecular support for a distinct D. radfordiana. Overall, there is modest genetic diversity found at the population level for all Dicerandra annuals. Microsatellite data support previously proposed hypotheses of hybridization between D. linearifolia var. linearifolia and D. odoratissima, but do not support such hypotheses for D. fumella and D. linearifolia var. robustior.