Stellar mass-metallicity relation (MZ_⋆ R). Mass-weighted average stellar metallicity ([M/H]_M) as a function of the total stellar mass for the galaxies regardless of their SFH type (left column), galaxies with ST-SFHs (centre column), and galaxies with LT-SFHs (right column) in voids (first row), filaments & walls (second row), and clusters (third row). The MZ_⋆ R (dashed blue lines for voids, dot-dashed green lines for filaments & walls, and solid red lines for clusters) is derived as the 50th percentile (thick lines) inside each stellar mass bin of 0.5 dex. The number of galaxies inside each stellar mass bin is shown in brackets at the bottom of the panels. The shaded areas represent the s.e.m., and the 16th and 84th percentiles (thin lines) show the dispersion of the MZ_⋆ R. The fourth row shows a comparison of the MZ_⋆ R between galaxies voids, filaments & walls, and clusters, together with the MZ_⋆ R from Gallazzi et al. (2005) as a reference. In the fifth row, we show the differences of the MZ_⋆ R (lines), together with the error of the difference (shaded areas). See the values reported in Tables E.1 and E.2.