Allopatric diversification and evolutionary melting pot in a North African Palearctic relict: The biogeographic history of Salamandra algira.

North Africa is a climatically and topographically complex region with unique biotic assemblages resulting from the combination of multiple biogeographic realms. Here, we assess the role of climate in promoting intra-specific diversification in a Palearctic relict, the North African fire salamander, Salamandra algira, using a combination of phylogenetic and population genetic analyses, paleoclimatic modelling and niche overlap tests. We used mitochondrial DNA (Cyt-b), 9838 ddRADseq loci, and 14 microsatellite loci to characterize patterns of genetic diversity and population structure. Phylogenetic analyses recover two major clades, each including several lineages with mito-nuclear discordances suggesting introgressive patterns between lineages in the Middle Atlas, associated with a melting pot of genetic diversity. Paleoclimatic modelling identified putative climatic refugia, largely matching areas of high genetic diversity, and supports the role of aridity in promoting allopatric diversification associated with ecological niche conservatism. Overall, our results highlight the role of climatic microrefugia as drivers of populations' persistence and diversification in the face of climatic oscillations in North Africa, and stress the importance of accounting for different genomic regions when reconstructing biogeographic processes from molecular markers.

Winners and Losers: Cordulegaster Species under the Pressure of Climate Change.

(1) Bioclimatic factors have a proven effect on species distributions in terrestrial, marine, or freshwater ecosystems. Because of anthropogenic effects, the changes in these variables are accelerated; thus, the knowledge of the impact has great importance from a conservation point of view. Two endemic dragonflies, the Balkan Goldenring (Cordulegaster heros) and the Two-Toothed Goldenring (C. bidentata), confined to the hilly and mountainous regions in Europe, are classified as "Near Threatened" according to the IUCN Red List. (2) Modeling the potential occurrence of both species under present and future climatic conditions provides a more accurate picture of the most suitable areas. The models were used to predict the responses of both species to 6 different climate scenarios for the year 2070. (3) We revealed which climatic and abiotic variables affect them the most and which areas are the most suitable for the species. We calculated how future climatic changes would affect the range of suitable areas for the two species. (4) According to our results, the suitable area for Cordulegaster bidentata and C. heros are strongly influenced by bioclimatic variables and showed an upward shift toward high elevations. The models predict a loss of suitable area in the case of C. bidentata and a large gain in the case of C. heros.

Establishing the Bases for Introducing the Unexplored Portuguese Common Bean Germplasm into the Breeding World.

Common bean (Phaseolus vulgaris L.) is among the most important grain legumes for human consumption worldwide. Portugal has a potentially promising common bean germplasm, resulting from more than five centuries of natural adaptation and farmers' selection. Nevertheless, limited characterization of this resource hampers its exploitation by breeding programs. To support a more efficient conservation of the national bean germplasm and promote its use in crop improvement, we performed, for the first time, a simultaneous molecular marker (21 microsatellites and a DNA marker for phaseolin-type diversity analysis) and seed and plant morphological characterization (14 traits) of 175 accessions from Portuguese mainland and islands traditional bean-growing regions. A total of 188 different alleles were identified and an average pairwise Cavalli-Sforza and Edwards' chord genetic distance of 0.193 was estimated among accessions. To relate the Portuguese germplasm with the global common bean diversity, 17 wild relatives and representative accessions from the Andean and Mesoamerican gene pools were evaluated at the molecular level. No correlation was detected between the variability found and the geographic origin of accessions. Structure analysis divided the collection into three main clusters. Most of the Portuguese accessions grouped with the race representatives and wild relatives from the Andean region. One third of the national germplasm had admixed genetic origin and might represent putative hybrids among gene pools from the two original centers of domestication in the Andes and Mesoamerica. The molecular marker-based classification was largely congruent with the three most frequent phaseolin haplotype patterns observed in the accessions analyzed. Seed and plant morphological characterization of 150 Portuguese common bean accessions revealed a clear separation among genetic structure and phaseolin haplotype groups of accessions, with seed size and shape and the number of locules per pod the most discriminant traits. Additionally, we used molecular and morphological data to develop a series of smaller core collections that, by maximizing the genetic and morphological diversity of the original collection, represents the Portuguese common bean germplasm with minimum repetitiveness. A core collection with 37 accessions contained 100% of the genetic variation found in the entire collection. This core collection is appropriate for a more detailed characterization and should be explored, as a priority, in national and international common bean breeding efforts. Furthermore, the identified intermediate accessions (with admixed genetic origin) may have novel genetic combinations useful in future bean breeding.