Phylogenetic relationships among Lauraceae, inferred from sequence variation in the chloroplast and nuclear genomes, suggest an early Gondwanan and Laurasian division. Descendants of the Gondwanan lineage form a minor element in the neotropical Lauraceae flora. Most neotropical diversity instead is accommodated in a large terminal clade that is nested within a paraphyletic assemblage of Laurasian lineages. Within this terminal clade, South American lineages form derived branches relative to clades restricted to Central America. This supports the morphology-based hypothesis of Rohwer and Kubitzki (1993) of a northern hemisphere origin and immigration into South America of part of the neotropical Lauraceae stock. But when did this immigration take place? The presence of African species of Ocotea near the base of the neotropical clade indicates that the initial southward movement occurred when terrestrial migration into Africa was also possible. Molecular clock estimates of the divergence of South American from Central American Lauraceae place the event at ~70 MYBP. This would be consistent with a Late Cretaceous invasion of South America —either from Central America via the Proto-Antilles arc or from Africa— followed by extensive radiation during the isolation of South America from the Upper Cretaceous to the Pliocene.

Key words: biogeography, Gondwana, Lauraceae, Laurasia, molecular clock, Ocotea