Graphical representation of the DS-test output. The plot shows the spatial location of the galaxies. The radii of the plotted circles are proportional to e^δ where δ is the DS-test measure of the local deviation from the global velocity dispersion and mean recessional velocity, i.e. larger symbols correspond to a higher significance of residing in a substructure. The colours indicate the rest-frame velocity relative to the cluster centre (BCG1) in km s^-1. BCG1 and BCG2 are marked by black crosses, respectively. Obviously there is some substructure detected in the south-east region of the cluster (indicated by the dashed lines). For a comparison with subcluster membership see Fig. 5.