Biogeography of Neotropical Meliaceae: geological connections, fossil and molecular evidence revisited

We here provide, first, a general introduction into the woody angiosperm family Meliaceae, including updated numbers of the genera and species found in different parts of the globe, paying attention to geographic centres of diversity and patterns of endemism. Second, and more specifically, we review the latest literature concerning land connections (i) between Eurasia and North America, (ii) between North America and South America, as well as (iii) dispersal paths between Africa and South America that have existed since the proposed evolutionary origin of modern Meliaceae, i.e. from the Upper Cretaceous onwards (ca. 100 Million years ago). Comparing geological evidence with the fossil record as well as biogeographic studies, there is indication that the nowadays pantropically distributed family has made use of all these three routes. Five out of the eight modern Neotropical genera have a fossil record, namely Carapa Aubl., Cedrela P. Browne, Guarea F. Allam., Swietenia Jacq., and Trichilia P. Browne. Carapa and Trichilia have a modern transatlantic disjunction (distribution in Africa, Central and South America), and a fossil record in Africa and North/Central America (Trichilia), or Africa and Eurasia (Carapoxylon). Cedrela has a rich fossil record in Eurasia and the Americas. The global decrease in temperatures and a lack of Cedrela fossils in North America from the Late Miocene onwards suggest the genus had gone extinct there by that time, leading to its modern distribution in Central and South America. Oligocene to Pliocene fossils of Guarea, Swietenia and Trichilia in Central American key regions support biotic interchange between North and South America at various times.

Automated summary

The article provides an overview of the woody angiosperm family Meliaceae, covering the genera and species found globally and their geographic distribution. It also reviews the land connections between different continents since the Upper Cretaceous period and discusses the dispersal paths between Africa and South America. Fossil records and biogeographic studies suggest the family has utilized these routes for distribution, with certain genera having transatlantic disjunctions and rich fossil records in different continents.