Chromosome counts for 26 species of Mexican composites are reported for the first time. These include first reports for 10 genera (Piqueria, Dicranocarpus, Flourensia, Montanoa, Sabazia, Zaluzania, Florestina, Loxothysanus,Palafoxia, and Sartwellia). Particularly noteworthy is the diploid chromosome count forSabazia humilis (n = 4), the lowest count so far reported for the subtribe Verbesininae. Chromosome numbers and morphological features indicate that the generaSartwellia andFlaveria are perhaps best placed with or close to the genusHaplöesthes. Various other realignments and/or relationships are tentatively suggested.