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The genus Pancovia comprises economically important plants native to Africa. Here, a systematic study was carried out on six species of Pancovia with a view to elucidate the significance of their characters for identification purposes. Morphological and leaf epidermis characters of the plants were assessed based on herbarium specimens. Useful diagnostic morphological features observed include leaf size, inflorescence length and fruit size. Variations also exist in the leaf epidermis characters examined. Polygonal cells and straight anticlinal wall were observed on the adaxial surface while the abaxial comprises irregular cells with undulate walls; exception is seen in P. atroviolaceus and P. harmsiana where the cells are irregular on both surfaces. The frequency of epidermal cells was higher on the adaxial compared to the abaxial surface and there is wide variation in the number of stomata recorded in each species. Stomata are anomocytic, sunken or raised with characteristic staining subsidiary cells and are restricted to the abaxial surface of the leaf. Based on the observed characters, a description of taxa studied and a dichotomous key is presented for their identification. This study can be seen as a contribution to the systematic literature available for the delimitation of Pancovia species in Africa. [ABSTRACT FROM AUTHOR]

Climate change is predicted to impact species’ genetic diversity and distribution. We used Senegalia senegal (L.) Britton, an economically important species distributed in the Sudano-Sahelian savannah belt of West Africa, to investigate the impact of climate change on intraspecific genetic diversity and distribution. We used ten nuclear and two plastid microsatellite markers to assess genetic variation, population structure and differentiation across thirteen sites in West Africa. We projected suitable range, and potential impact of climate change on genetic diversity using a maximum entropy approach, under four different climate change scenarios. We found higher genetic and haplotype diversity at both nuclear and plastid markers than previously reported. Genetic differentiation was strong for chloroplast and moderate for the nuclear genome. Both genomes indicated three spatially structured genetic groups. The distribution of Senegalia senegal is strongly correlated with extractable nitrogen, coarse fragments, soil organic carbon stock, precipitation of warmest and coldest quarter and mean temperature of driest quarter. We predicted 40.96 to 6.34 per cent of the current distribution to favourably support the species’ ecological requirements under future climate scenarios. Our results suggest that climate change is going to affect the population genetic structure of Senegalia senegal, and that patterns of genetic diversity are going to influence the species’ adaptive response to climate change. Our study contributes to the growing evidence predicting the loss of economically relevant plants in West Africa in the next decades due to climate change. [ABSTRACT FROM AUTHOR]