Virial parameter vs. SFR surface density (α_vir − Σ_SFR) of H II regions (left), colored by stellar mass. The solid line represents the best-fit α_vir − Σ_SFR relation. Stellar mass surface density – stellar age (Σ_* − age) distribution of H II regions (right), colored by SFR surface densities. The solid lines show the best-fit relations of Σ_* − age in the two component galaxies NGC 4809 and NGC 4810. The other markers are the same as in Fig. 7.