Genus delimitation in Andropogoneae (Poaceae): what has been resolved and what still needs to be done?

Resumen

The tribe Andropogoneae (Poaceae: Panicoideae) is one of the most complex lineages among grasses, both morphologically and phylogenetically. Reticulate evolution and polyploidy are common in this group, as well as the lack of clear morphological discontinuities between taxa, which complicates the delimitation of its genera and species. Despite the great ecological and economic importance of Andropogoneae, many taxonomic uncertainties remain regarding the circumscription of genera within the tribe. Recent phylogenetic studies have shown that many traditionally accepted genera in Andropogoneae are para- or polyphyletic, requiring taxonomic rearrangements to ensure monophyly. Phylogenies based on plastome and nuclear data have contributed to the delimitation of some of these taxa, such as the recognition of Tripidium as a genus distinct from Saccharum. Similarly, Anatherum was recently reestablished and expanded to include about one-third of the species formerly accepted in Andropogon. Molecular phylogenies have also revealed that Themeda should incorporate at least a few species of Heteropogon to achieve monophyly. Future studies should focus on the delimitation of genera such as Andropogon, Eulalia, Ischaemum, Mnesithea, Saccharum, and Schizachyrium. Several changes in the circumscription of genera within Andropogoneae are expected in the coming years. Funding: FAPEMIG, CNPq.

Citation: Dorneles Welker, C.A., McKain, M.R., Peichoto, M.C., Arthan, W., Vorontsova, M.S. & Kellogg, E.A. 2025. Genus delimitation in Andropogoneae (Poaceae): what has been resolved and what still needs to be done? Revista Jard. Bot. Nac. Univ. Habana 46(Número especial 1): 68.  

Trabajo presentado en el XIII Congreso Latinoamericano de Botánica. Sesión Sistemática, Filogenia, Biogeografía y Evolución.