A genus of about 1250 species, herbs, shrubs, and (rarely) trees, of nearly cosmopolitan distribution (primarily tropical and warm-temperate). Webster (1992, 1993a) considered the 2 taxa traditionally treated as Crotonopsis to be closely related to sections within Croton, such as section Gynamblosis; his reasoning has been supported by molecular phylogenetic studies and all recent floristic treatments and is followed here. The subgenera and sections shown in the key follow van Ee, Riina, & Berry (2011).
Ref: Govaerts, Frodin, & Radcliffe-Smith (2000); Ungberg (2022) In Weakley et al. (2022); van Ee & Berry (2009); van Ee & Berry (2010); van Ee & Berry (2016) In Flora of North America Editorial Committee (2016); van Ee, Berry, & Ginzbarg (2011); van Ee, Riina, & Berry (2011); Ward (2012a); Webster (1992); Webster (1993a); Webster (2014) In Kubitzki (2014). Show full citations.