Mass-size relation for the CIELO galaxies defined by the stellar half-mass radius, R_hm, as a function of the B/T ratio. More disc-dominated galaxies have larger sizes at a given stellar mass as expected. The median observed trends for late-type (LTG; dashed blue lines) and early-type galaxies (ETG; dashed red lines) reported by van der Wel et al. (2014) are shown (shaded regions are determined by the 25–75th percentiles (LOESS).