Taxonomic aspects of Croton L. (Euphorbiaceae) in the Southeast region of Brazil

Abstract

The Croton L. genus is the second largest and most diverse of the Euphorbiaceae with around 1,200 species, grouped in 40 sections, with pantropical distribution, of which the majority occur in the Americas. In South America, Brazil is the country which congregates the greatest number of species, approximately 356. Of these, 172 are found in the southeast region, this being probably, the center of diversity of the genus. Croton is a good example of the “genus problem” - which is big and taxonomically complex - and perhaps for this reason it has been neglected in favor of smaller and more clearly defined genuses. Due to the large size and diversity, no complete taxonomic treatment for the genus has been undertaken since Prodromus and, in Brazil, the Flora brasiliensis. Thus, in many herbariums in Brazil (and in the world), it is common to find a large quantity of non-identified (or badly identified) Croton collections at the level of species, which require, urgently, a discerning taxonomic study. Thus, in order to contribute to the better understanding of the taxonomic aspects and the phylogeny of Croton on a global scale, it is intended to carry out the floristic and taxonomic survey of Croton in the southeast region, in pursuit of a better understanding and circumscription of the species, as well as the survey of information on the morphology, biology, biogeography, among others, trying to gather the greatest number of features, including molecular so that subsequently they may be used in cladistic analyses of the group. All the collected samples will be georeferenced and the data included in the database of the Biota-FAPESP Program. (AU)