Morphological diagnostic diagrams representing the following relations: M₂₀ (moment of light) vs. C (Abraham concentration index) (top left), M₂₀ vs. C_BC (Bershady-Conselice concentration index) (top right), C vs. C_BC (centre left), GINI (Gini coefficient) vs. C_BC (centre right), and log C vs. log  A (asymmetry) (bottom). Blue spirals represent galaxies classified as LT, and red ellipses as ET, while light and dark colours refer to galaxies fainter and brighter than 23 mag in r′, respectively. Typical errors of all these parameters are comparable to or lower than the symbols’ size. Histograms show the morphological parameter distribution for each type, the red solid line is for ET galaxies and the blue dashed one for LT galaxies.