Contrasting leaf cuticular wax composition of Conchocarpus and Dryades species (Rutaceae) from the Atlantic Forest and “Restinga”

Conchocarpus is the largest genus in the subtribe Galipeinae, tribe Galipeeae, distributed from Nicaragua to northern Bolivia and southern Brazil, with the center of species diversity in the Brazilian Atlantic Rainforest. Five species were recently segregated to a new genus ( Dryades ), thereby restoring the monophyly of Conchocarpus sensu stricto. In addition to the wide morphological diversity of Conchocarpus species, to date, few chemical aspects have been explored, mainly in regard to wax composition. This study aims to compare the chemical composition of the cuticular wax of selected species of Conchocarpus sensu stricto and Dryades , in order to determine their similarities and/or differences, as well as discuss possible correlations with habitats, and potential taxonomic implications. The main results showed that in general, Conchocarpus and Dryades could be distinguished, with species of the former genus exhibiting longer-chain alkanes and those of the latter higher triterpene diversity. Moreover, species inhabiting the Atlantic Rainforest have a thinner wax load, reduced amounts of triterpenes and are rich in alkanes, while those from “Restinga” vegetation exhibit a higher wax content, fewer alkanes, and large amounts of triterpenes.