Composite image of the 37 galaxies drawn from the PHANGS surveys, ordered following their Hubble morphological T-type from the LEDA database, from massive spirals to low-mass irregular galaxies. All the maps have been convolved to the resolution of the ALMA/CO(2–1) maps, corresponding to the minimal aperture size reported in Table B.1. The white masks show regions that are excluded from our analysis (Hα and CO bright peaks identified in K22 as well as artifacts and diffraction spikes in any of the three tracers). The green circles show the brightest peaks in 21 μm, which are masked in our analysis, as described in Section 3.1. The number of masked peaks and corresponding surface brightness thresholds are reported in the Table B.1.