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Abstract: The neotropical genus Fosterella L.B. Smith (Pitcairnioideae, Bromeliaceae) comprises about 30 species, with a centre of diversity in semiarid to humid habitats of the Andean slopes and valleys of [...]

In the Atlantic Rainforest located north of the São Francisco River (northeast Brazil), the humid enclaves called brejos de altitude play a significant role in the diversity dynamics of local flora and fauna. The related species Dyckia pernambucana and D. limae (Bromeliaceae) are characterized by their narrow endemic occurrence in such brejos, and their species status remains unclear. In order to understand the species delimitation in those assigned taxonomic entities, patterns of gene flow and genetic variability were calculated using nuclear and plastid microsatellites and AFLP markers. In this regard, we collected populations of the Pernambuco complex (D. limae and D. pernambucana , from the Borborema Plateau) and the closest relative D. dissitiflora (from the northern Espinhaço Range). Genetic diversity was moderate, despite the possible influence of genetic drift and selfing rates. Dyckia limae could not be undoubtedly discriminated from the remaining populations of Pernambuco, and we propose the synonymization of these species. Thus, the conservation of D. limae as a formerly single species would not reflect the conservation of the minimal gene pool of the studied lineage (D. pernambucana). We also propose the revalidation of the conservation status of this species, endemic to anthropomorphic island-like mountains environments. Finally, the associations found here were consistent with the historical patterns of colonization and fragmentation of the Atlantic Rainforest. [ABSTRACT FROM AUTHOR]

The terrestrial bromeliad Fosterella rusbyi is endemic to the Bolivian Andes, where it mainly grows on steep, exposed slopes along roadsides and riverbeds in the seasonally dry tropical forest (SDTF) and the mesic montane forest (Yungas) biomes. We hypothesize that allopatric speciation may have been a main driver of diversification in Fosterella since the Miocene and that the scattered distribution of suitable habitats fostered the evolution of the high degree of endemism observed today. To provide further information relating to this hypothesis, we analysed the partition of genetic diversity and the extent of gene flow among natural populations of F. rusbyi using plastid and nuclear microsatellite markers. Nineteen plastid haplotypes were found, but the mean haplotype diversity per population was low. Nuclear microsatellite markers revealed 177 different multilocus genotypes (MLGs), of which 31 occurred in more than one plant. Recurrent MLGs were found in 76 plants that were therefore identified as clones. A considerable deficit of heterozygotes was detected at all nuclear loci. Geographical and genetic distances between populations were only weakly correlated with each other. Genetic divergence between populations was extremely high for both marker classes, suggesting that seed and pollen flow are low, even over short distances. The observed patterns are consistent with our hypothesis that newly available sites are sporadically colonized by one or a few founders, followed by in situ population expansion via vegetative propagation, self-pollination and/or biparental inbreeding, genetic differentiation among persistent populations and, ultimately, allopatric speciation. [ABSTRACT FROM AUTHOR]

Premise of the Study: Microsatellite markers were developed in Deuterocohnia longipetala (Bromeliaceae) to investigate species and subspecies boundaries within the genus and the genetic diversity of natural populations. Methods and Results: We used 454 pyrosequencing to isolate 835 microsatellite loci in D. longipetala. Of 64 loci selected for primer design, 15 were polymorphic among 23 individuals of D. longipetala and 76 individuals of the heterologous subspecies D. meziana subsp. meziana and D. meziana subsp. carmineo‐viridiflora. Twelve and 13 of these loci were also polymorphic in one population each of D. brevispicata and D. seramisiana, respectively. Numbers of alleles per locus varied from two to 14 in D. longipetala, two to 12 in D. meziana, one to nine in D. brevispicata, and one to 10 in D. seramisiana. STRUCTURE analyses clearly separated the taxa from each other. Conclusions: The 15 new microsatellite markers are promising tools for studying population genetics in Deuterocohnia species. [ABSTRACT FROM AUTHOR]

We report the genetic diversity and population structure of the Yellow-bellied Toad (Bombina variegata) at the northern edge of its distribution range in northern Hesse, Germany. A total of 281 samples from 20 populations were analysed, using six polymorphic nuclear microsatellite markers (ncSSRs). Moderate genetic diversity (He = 0.37-0.59) was detected within these B. variegata populations. We found evidence of a distinctive population structure, with populations at the edge of the study area showing lower degrees of diversity and higher degrees of isolation than more central populations. No genetic differentiation was found between populations from the middle Fulda and Werra river valleys, suggesting that fragmentation, e.g., by the A4 highway that separates the two river valleys, has not yet had genetic consequences. Furthermore, indications of an isolation-by-distance pattern was found, suggestive of restricted gene flow between the studied populations. To ensure the long-term survival of the Yellow-bellied Toad in northern Hesse, we recommend continuous management efforts that focus on the reconnection of isolated populations and continuation of demographic population monitoring supplemented by population genetic analyses. [ABSTRACT FROM AUTHOR]

Dyckia is a xeromorphic bromeliad genus with 168 species distributed throughout south-eastern South America, with the centre of diversity in Brazil. Previous phylogenetic studies based on sequence data revealed, in general, poor resolution among species. To improve our understanding of infrageneric relationships, here we present a molecular phylogenetic analysis of Dyckia based on amplified fragment length polymorphism (AFLP) markers. We also discuss the evolution of floral characters and their implications for the life-history of the genus. Dyckia proved to be well supported as a monophyletic group, although showing a poor resolution in the backbone of the tree. In accordance with previous data, our results suggest that hybridization and introgression have played a significant role in the evolution of the genus. However, the AFLP data showed stronger support for terminal nodes. The results provided deeper insights into the infrageneric relationships, the correlation between species groups, morphological aspects and geographical distribution. Additionally, the character reconstruction corroborates the geographical association found, in which a pattern could generally be observed for species stated as early diverging. Analysing the genus at a population level and taxonomic revision are crucial to understanding the evolutionary dynamics of the clade. [ABSTRACT FROM AUTHOR]