Standard emission-line diagnostic diagram for CALIFA galaxies with SDSS spectra. Only spectra centered on the galaxy nucleus (<3′′) and with S/N > 3 in all emission lines are shown here. The demarcation lines by Kewley et al. (2001; black), Kauffmann et al. (2003b; black dotted), and Cid Fernandes et al. (2010; yellow) are used to characterize the objects into star forming (black), Seyferts (red), SF/AGN intermediates (blue), and LINER-like (orange) objects. The number of objects per class is indicated on the plot.