ALMA CO(2–1) integrated intensity (moment 0) maps, with pixel masking applied to the data cube (top left panel) and without it (top right panel), CO(2–1) velocity dispersion (moment 2) map (bottom left panel) and the HST Paα image (bottom right panel) of the galaxy NGC 3110 at ∼100 pc scale. At this scale, significant differences are observed between the CO(2–1) moment 0 and Paα maps, revealing emission structures distributed throughout the galaxy.