MorCat color-magnitude diagrams in square cells of color and magnitude of length 0.25. To retrieve a representative picture of nearby galaxies, galaxies were randomly drawn from the MorCat ∩ GALEX sample in 1 mag intervals of M_r, in order to match the M_r distribution of MorCat. Left panel: distribution of all MorCat galaxies, whereas the right panel is restricted to galaxies with an aspect ratio ≥0.61, in order to exclude highly inclined and edge-on disks. Both graphs display the bimodal distribution of galaxy population with the two density peaks of the Red Sequence and the Blue Cloud, separated by the Green Valley or Green Valley. The dashed lines in the right panel delimit the regions of the Red Sequence, the Green Valley, and the Blue Cloud that are respectively used in Sect. 4.1.2 to illustrate the stretching of the NUV−r that generates the Green Valley, and lead us to rename it Green Plain.