We have distinguished between morphological features that can be directly attributed to past merger activity in the galaxy (“Merger-related”) from those that are not strictly related to mergers or cannot be observationally attributed to them. Tidal satellites are provided in “Miscellanea” because, although they are produced by interactions and mergers by definition, it is difficult to establish the tidal nature of the satellites orbiting a galaxy just through visual inspection if the system is relaxed. We have preferred not considering them as merger relics (for more details, see Sect. 7.3).

The percentages in the major- and minor-merger subsamples are computed independently for each one, considering a total of 67 S0-like remnants coming from major mergers and a total of 29 S0 ones from minor mergers.

The gS0 progenitor of the minor merger experiments is strongly barred. There is only one S0 major-merger remnant with traces of a large bar (gSbgSbo72), but so diluted that we have not considered it as significant (see Sect. 7.1).

The statistics for the S0-like remnants “with merger relics” include all remnants with one or more morphological features observable in the artificial photometric images pointing to their past merger origin. Those “with no traces of past merger” show none.