Scaling relations for the Virgo cluster galaxies (in the g band). In the three panels from left to right, the luminosity (L_g) is plotted with respect to the surface brightness at the effective radius (Σ_e), the mean surface brightness within the effective radius (⟨Σ⟩_e), and the effective radius (R_e), respectively. The black dots are all the galaxies in the NGVS catalog. The filled red and open blue circles show the selected samples of UDGs and diffuse galaxies, respectively. The dotted and dashed black curves show the mean scaling relations and their 2σ confidence limits, respectively, based on Lim et al. (2020). The solid gray line marks the UDG selection cut of van Dokkum et al. (2015) with μ_0, g > 24 mag arcsec⁻² and R_e, g > 1.5 kpc for comparison.