Genetic diversity and phylogeographic patterns of the dioecious palmChamaedorea tepejilote(Arecaceae) in Costa Rica: the role of mountain ranges and possible refugia

A novel phylogeographic pattern of gene flow between Caribbean and Pacific populations of the understory palm Chamaedorea tepejilote was uncovered, suggesting historical connectivity through the southern Talamanca Mountain range in Panama. This challenges previous assumptions about dispersal pathways in Lower Central America (LCA). The study used nuclear SSR and chloroplast DNA markers to analyze genetic diversity across 18 populations in Costa Rica, revealing moderate to high nuclear genetic diversity but eroded cytoplasmic diversity, likely due to habitat fragmentation and population declines. High-elevation mountain ranges acted as significant barriers to gene flow, though low-elevation passes allowed connectivity. The findings highlight the role of mountain ranges in shaping Neotropical plant phylogeography and underscore the importance of this first phylogeographic study for the genus Chamaedorea.

Fuchs, E. J., Cascante-Marín, A., Madrigal-Brenes, R., & Quesada, M. (2022). Genetic diversity and phylogeographic patterns of the dioecious palmChamaedorea tepejilote(Arecaceae) in Costa Rica: the role of mountain ranges and possible refugia. AoB PLANTS, 15(1). https://doi.org/10.1093/aobpla/plac060