The M_r − (g − i) − R_eff − ⟨μ⟩_eff-plane of BCDs and ETGs. No decomposition into starburst and LSB-component was applied. Red squares represent the primary BCD sample, blue squares denote the candidate sample. Black dots represent the sample of early-type galaxies taken from Janz & Lisker (2008, 2009), for which colours were derived from the light within 2R_eff. Green asterisks are dE(bc)s from Lisker et al. (2006b). For each (vertical) interval in magnitude or surface brightness, the (horizontal) ± 2σ-region of the ETGs is indicated by the black bars. VCC 0428 and 1313 have colours ((g − i)_tot =  −0.049 and −0.263mag, respectively), lying outside the colour range of the plot and are therefore only indicated by an arrow.