There are approximately 170 to 180 genera in the Eupatorieae. The following list of 182 genera is from Hind and Robinson (2007). They do not recognize the genus Eutrochium, but put those 5 species in Eupatorium.
The largest genera and the approximate number of species in each are: Mikania (400), Ageratina (265), Stevia (200), Chromolaena (165), Koanophyllon (120), Brickellia (100), and Fleischmannia (95).
In 1987, Robert M. King and Harold E. Robinson wrote a book on Eupatorieae. In this book, they divided the tribe into 17 subtribes. These are Hofmeisteriinae, Oxylobinae, Mikaniinae, Trichocoroninae, Adenostemmatinae, Fleischmanniinae, Ageratinae, Eupatoriinae, Liatrinae, Praxelinae, Gyptidinae, Disynaphiinae, Ayapaninae, Alomiinae, Critoniinae, Hebecliniinae, and Neomirandeinae.
In 1994, Kare Bremer did a cladistic analysis of Eupatorieae in his book on the family Asteraceae. He recognized only 16 subtribes, subsuming Neomirandeinae into Hebecliniinae.
In 2007, D. J. Nicholas Hind and Harold E. Robinson covered Eupatorieae for The Families and Genera of Vascular Plants. They recognized the same 17 subtribes that King and Robinson had recognized in 1987.
The division of this tribe into subtribes is provisional and likely to change when more data, especially DNA sequence data, becomes available.
No DNA study has yet included a large number of species and sampled widely in Eupatorieae, but 3 studies have investigated Eupatorium and its relatives within the tribe. These 3 studies are the basis for the phylogeny shown below.
In some of the older works, the genus Eupatorium has been circumscribed to include as many as 1200 species, over a third of the species in the tribe. In more recent works, Eupatorium has been defined to contain about 40–45 species, with the main differences between authors being whether to include Eutrochium and whether certain populations should be considered species, varieties, or hybrids.
As more becomes known about the Eupatorieae, other genera will surely have to be revised as well.
A partial phylogeny of the tribe (focusing on Eupatorium and some of the other North American genera) is:
From the positions of Stevia and Stomatanthes in the phylogeny, it is obvious that some of the subtribes are probably polyphyletic. Many of the branches in the tree above have only weak statistical support, so this tree can not serve as a basis for re-classification. For convenience, the genera will remain in their current subtribes until a much larger data set enables the production of a more robustly supported phylogeny.
^ abcdD.J.N.Hind & H.E.Robinson. 2007. Tribe Eupatorieae In: The Families and Genera of Vascular Plants vol.VIII. (Joachim W.Kadereit & Charles Jeffrey, volume editors. Klaus Kubitzky, general editor). Springer-Verlag. Berlin, Heidelberg.
^Panero,J.L. & Funk,V.A. (2008). "The value of sampling anomalous taxa in phylogenetic studies: Major clades of the Asteraceae revealed". Molecular Phylogenetics and Evolution 47 (2): 757–782. doi:10.1016/j.ympev.2008.02.011. PMID18375151.
^Robinson,H.E. 2002. "New supertribes, Helianthodae and Senecionodae, for the subfamily Asteroideae (Asteraceae)". Phytologia 86(3):116-120
^Panero,J.L., & Funk,V.A.. 2002. "Toward a phylogenetic subfamilial classification for the Compositae (Asteraceae)". Proceedings of the Biological Society of Washington 115(4):909-922
^D.J.Mabberley. Mabberley's Plant-Book third edition (2008). Cambridge University Press.
^Robinson, Harold; Pruski, John (2013). "Zyzyura, a new genus of Eupatorieae (Asteraceae) from Belize". PhytoKeys 20: 1–7. doi:10.3897/phytokeys.20.4033.
^King,R.M., and Robinson,H.E. 1987. The Genera of Eupatorieae Missouri Botanical Garden Monographs in Systematic Botany 22:1-581. Missouri Botanical Garden/Allen Press. Lawrence, Kansas, USA.
^Ito,M., Watanabe,K., Kita,Y., Kawahara,T., Crawford,D.J., and Yahara,T. 2000. "Phylogeny and Phytogeography of Eupatorium: Insights from sequence data of the nrDNA ITS regions and cpDNA RFLP". Journal of Plant Research 113(1109):79-89.