Genetic breaks caused by ancient forest fragmentation: phylogeography of Staudtia kamerunensis (Myristicaceae) reveals distinct clusters in the Congo Basin

Abstract Documenting species and population diversity is becoming increasingly important as the destruction degradation of natural ecosystems are leading to a worldwide biodiversity loss. Despite rapid development genetic tools, many remain undocumented little known about individuals populations, especially for tropical African plants. In this study, we aim identify putative hidden and/or differentiated populations in tree Staudtia kamerunensis Warb. (Myristicaceae), widespread characterized by high morphological complex taxonomical history. Historical herbarium vouchers were sampled leaf or cambium samples collected field, dried silica gel, subsequently genotyped at 14 microsatellite loci (SSRs), well sequenced two nuclear genes ( At103 , Agt1 ) one plastid region psbA-trnH ). These data then analyzed using Bayesian clustering, genetics, construction haplowebs assess clustering patterns, distribution diversity, differentiation among populations. Multiple genetically clusters observed parapatry throughout Central Africa. Genetic was similar these clusters, apart from most southeast Democratic Republic Congo (DR Congo), which showed lower levels diversity. The breaks detected between S. likely not indicative but rather result ancient rainforest fragmentation during cold dry periods Pliocene Pleistocene. strong divergence DR could be an ongoing speciation linked ecological niche differentiation.