Top panel: gas mass versus stellar mass for a sample of galaxies in the Local Universe. LITTLE-THINGS, SPARC and THINGS galaxies are marked by triangles (in orange, grey, and blue, respectively). Local low surface brightness galaxies (LSBGs) from McGaugh (2011, 2017, 2021) are in green, and UDGs in cyan. LSB-D is marked by the red circle. The dashed line marks the 1 : 1 linear relation. Bottom panel: the baryonic Tully-Fisher relation of Local Group dwarf and spiral galaxies (dashed line; McGaugh et al. 2021). Symbols are as in the top panel. For the Local LSBGs sample, pressure supported dwarfs (plotted against their velocity dispersion, σ_v) are marked by light green squares, while green triangles mark rotationally supported galaxies, plotted against their rotational velocity, v_rot.