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See list of 11 species in this genus

The traditionally defined genus Eupatorium has been dismantled into smaller, homogeneous, and monophyletic groups based on morphological and phylogenetic evidence (see also the genera Ageratina and Eutrochium). Most authors’ treatments of Eupatorium (including the one referenced here) suffer from poor taxonomy—they repeatedly treat hybrid-derived taxa as a variety of one of the putative parents, a system that creates obvious conflicts due to its non-monophyletic and arbitrary nature (i.e., which parent should the hybrid be allied to, and on what basis?). Hybrid-derived taxa are here treated as species because they are reproductively competent and can be found outside of the range of parental co-occurence. Reference: Siripun and Schilling (2006).

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 Show photos of:   Each photo represents one species in this genus.