Southeastern region of the Suprime-Cam R_C-band image of the cluster MACS0329 (north top and east left) showing the group region within 0.5 R₂₀₀ ∼ 2.4′ (enclosed in the large, thick green circle). The thin green circle indicates the 1′ radius region (1′∼160 kpc at the group redshift). Galaxies with available redshift are highlighted with small circles, in particular red or cyan circles in the case of members or nonmembers according to the selection procedure (see Sects. 2 and 3). Labels indicate objects discussed in the text.