Aim Using the Acalyphoideae, we explore the origin and diversification of the Caribbean flora. This lineage of flowering plants constitutes an important component of the flora of the Caribbean islands with many endemics. Furthermore, because it is also diverse in adjacent Mexico, Mesoamerica and South America, it allows a representative analysis of possible migration routes into the Caribbean. Location Neotropics, Cuba, Hispaniola and the Caribbean region, Mexico and Mesoamerica. Methods We generated a well‐resolved and dated phylogenetic hypothesis based on a dense sampling, in particular of the New World taxa but also representing all remaining Acalyphoideae, and combined datasets of chloroplast spacers and introns. Bayesian divergence‐time estimation was applied to determine node ages. Ancestral states of distributional areas were reconstructed in a Bayesian framework to determine the geographical origin of the Caribbean ancestors. Results A Neotropical clade started to diversify 59.29 [50.41–68.44 95% highest posterior density (HPD)] Ma within the Acalyphoideae. The Caribbean islands then were reached several times independently from the Miocene onwards. The exclusively Caribbean Leucocroton–Lasiocroton–Garciadelia [9.1 (6.3–12.3 95% HPD) Ma] and Acidoton–Platygyna [9.3 (5.2–15.4 95% HPD) Ma] clades exhibit one of the most successful plant radiations in the region, and Caribbean subclades of Acalypha and Bernardia just date back to the Pliocene and Pleistocene, respectively. Main conclusions Our data show that Mexico and Mesoamerica have played a key role as a source for today's Caribbean Acalyphoideae. Their ancestors arrived from the mainland to the Caribbean islands during the Miocene when Caribbean land masses were completely separated and then diversified in situ. We postulate long‐distance dispersal to have played a major role for colonizing the Caribbean.

A comparative study of leaf architecture and anatomy of 42 species of Bernardia and other genera related of Acalyphoideae was undertaken to identify characters that support infrageneric and specific delimitation. Thirty variable foliar architectural and anatomical characters were studied. Some characters are consistent (e.g., venation pattern, secondary and tertiary vein arrangement, presence or absence of agrophic veins, type of areoles, bundle sheath cell type, presence or absence of fibers in the mesophyll, trichome type, stomata location, and type of crystals), and characterize genera. In addition, foliar character distribution within Bernardia supports the most recent infrageneric classification.

An updated checklist of the Mexican species of Dalbergia (Leguminosae) to aid in its conservation effortsUn listado actualizado de las especies mexicanas de Dalbergia (Leguminosae) para ayudar en los esfuerzos para su conservación

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