Fraction of EFIGI ∩ GALEX galaxies with Incl-Elong ≤ 2 having an attribute value of Hot Spots > 0. The attribute measures the relative intensity of regions with a very high surface brightness. Galaxies are binned in cells of 0.75 dex in stellar mass and 0.75 in NUV−r color. The sample size as well as the error on the mean are indicated in each cell. Cells with less than 10 galaxies are discarded, and the graph is limited to NUV−r ≤ 4.25, as the fraction of Hot Spots > 0 is below 5% for redder galaxies.