Example phase-space distributions of cluster galaxies. Left panel: Spatial distribution of the member galaxies of 1eRASS J004207.0-283154 on the projected sky. Red upward triangles and blue downward triangles represent receding and approaching galaxies, respectively. Black points are galaxies without spectroscopic redshift. Right panel: Line-of-sight velocities of the member galaxies with respect to the BCG against the projected radii, r_proj. Galaxies with only photometric redshift are excluded in this plot. Cluster 004207.0-283154 presents a slightly asymmetric velocity distribution of its member galaxies. This does not affect the binned velocity dispersion, as galaxies within each bin were fit using the generalized Gaussian function, which allows a variable mean velocity (see Sect. 4.2).