
Trichomes are epidermal outgrowths generally associated with protection against desiccation and herbivores. These structures are widely distributed on plant parts but evolutionary studies of trichomes are still scarce. Nogueira et al. integrate phylogenetic and morpho-anatomical data in a study on the evolutionary history of the tribe Bignonieae in order to understand current patterns of diversity of trichome types. They find considerable topological variation in the evolution of glandular and non-glandular trichomes, suggesting that the most recent common ancestor of Bignonieae probably presented different trichome types on different plant parts. The descriptions and ontology presented will greatly facilitate comparisons between morphological variants and functional studies of trichomes.