Essential ecosystem services are provided by rainforests, which play a pivotal role in sustaining life on Earth. Habitat and biodiversity loss is an imminent threat to tropical rainforest regions worldwide because of agricultural development, mining, overexploitation of timber, and climate change. To ensure their continued adaptability and resilience in a changing world, it is imperative to preserve genetic diversity within tropical rainforest species. Within the smaller context of French Guiana, the specters of climate change, affecting temperature and rainfall, pose unprecedented challenges to this ecosystem, including on the hyperdominant tree species, Dicorynia guianensis (Fabaceae). The genetic data suggests a significant differentiation of populations in the western part of French Guiana and a demographic history of populations that is regionally variable. New genome resequencing data allows us to examine regional-scale genomic signatures of adaptation to climate and soil in this drought-sensitive species and to model genetics-informed distribution range projections under future climate regimes. The local-scale family structure will be better understood with High-throughput SSR-Seq data, which may explain differences between sites in colonization dynamics and local-scale spatial genetic structure. We can develop conservation strategies that can adapt to the challenges posed by future climate scenarios by understanding genetic responses to climate change.