A(Li) vs. the two age scales used in this work (see Sect. 2) for stars with planets (Y). Left panel: age from the literature (Age_Lite). Right panel: age from isochrones (Age_Param). The vertical lines represent the main galactic events known to happen in that temporal range (Sagittarius dwarf pericentres and the star formation burst presented in Mor et al. 2019). Consistent with previous figures, the grey shaded region corresponds to the transition region we called the isthmus.