Global biogeographic patterns of the genus Indigofera (Fabaceae: Indigofereae)

A comprehensive phylogenetic and biogeographic analysis of the genus Indigofera (Fabaceae) reveals that the tribe Indigofereae originated in the Africa-Madagascar region around 38 million years ago, with mainland Africa serving as the primary diversification center. The study, based on a newly assembled ITS phylogeny, identifies four main clades—Cape, Tethyan, Pantropical, and Paleotropical—with the Cape Clade being narrowly endemic to the Greater Cape Floristic Region (GCFR) of southwestern South Africa, while the others exhibit broader global distributions. Long-distance dispersals from Africa to South America, Australia, and Asia occurred during the late Miocene, facilitated by arid corridors in northeastern Africa and Arabia. The research underscores the critical role of the global Succulent biome in shaping Indigofera's biogeographic patterns, highlighting its influence on dispersal and diversification.

Du Preez, B., Schrire, B. D., Dreyer, L. L., Stirton, C. H., Chimphango, S. B. M., & Muasya, A. M. (2025). Global biogeographic patterns of the genus Indigofera (Fabaceae: Indigofereae). Brazilian Journal of Botany, 48(1). https://doi.org/10.1007/s40415-024-01045-4