Three circular areas around the extended filaments with the highest galaxy density, denoted area A, B, and C. Upper plot: Map showing the galaxy foreground temperature model from H2023. The model shows high galaxy density of nearby (z < 0.017) galaxies as low temperature. Red dots show the positions of massive (> 10¹³ M_⊙) galaxy groups containing large spiral galaxies within z < 0.02. The significance of the profile depth in Planck SMICA maps with ℓ ≤ 5 removed for spiral galaxies within the given zone is quoted in standard deviations calibrated on 10 000 simulations. Middle and lower plot: Projected distribution of filaments for the redshift range z ∈ [0.004, 0.02] for both the total sample (middle panel) and the highest linear K-band luminosity density (lower panel). The dotted pink lines represent 2MRS galaxies with a perpendicular distance of less than 4 Mpc to the filaments.