HRD of the Chamaeleon star-forming region compared to the grid of isochrones and tracks from pre-main sequence stars models. The green solid and black dashed lines denote the isochrones and tracks for each model, respectively, with the ages (in Myr) and masses (in M_⊙) indicated in the panels. The different colours and symbols represent the Chamaeleon subgroups discussed throughout this paper. The most massive star in our sample, namely Gaia DR2 5201128124701636864, is not shown here to improve the visibility of the low-mass stars that largely dominate our sample.