Top: Sample definitions in the redshift-stellar mass plane. In the analysis, we considered the samples encompassed by the colored boxes. The white boxes depict previously defined SDSS and GAMA-based galaxy samples (Farrow et al. 2015; Zu & Mandelbaum 2016). The line log10(M * ) = 5(z − 0.05)^0.45 + 8 corresponds to the volume limit used in this work. The colorbar depicts the number of galaxies in hexagonal (for better visualization) bins. Bottom: Area covered by the sample with log₁₀(M^*/M_⊙) > 10 and 0.05 < z < 0.18. The filamentary nature of the large-scale structure is visible. The orange (grey) area is (not) included in the eROSITA_DE footprint.