To evaluate whether host specialization is associated with parasite occurrence on different hosts (Q2), we calculated the fraction of parasites observed on a particular host, relative to all parasites with an identified host within 50 km from locations of origin of S. hermonthica populations tested in experiments. Starting from an initial set of S. hermonthica occurrence records (Bellis et al. 2020), we obtained subsets of records occurring specifically in fields of sorghum (n= 262), millet (n = 157), or maize (n = 74) according to specimen label data. Although millets include several unrelated species, 46 of 47 herbarium specimens with host identified as “millet” and that also gave the name of a genus indicated Pennisetum spp. rather than Eleusine, Setaria, Digitaria, Panicum, or other less common genera of cultivated “millets”. Combined with greater overlap in the distribution of pearl millet growing areas and the range of S. hermonthica (National Research Council 1996), our analyses are probably most reflective of parasites on pearl millet.