Line ratio maps overplotted with classification contours and the major axis of the primary (thin line) and the secondary bar (thick line). Left and center: areas surrounded by the black contour line correspond to AGN-like ionization. Areas enclosed by the red contour line contain regions classified as star forming. Other regions are dominated by composite-type line ratios. The classification was made according to the diagnostic diagram, the extreme starburst demarcation line of Kewley et al. (2001), and the pure star-formation demarcation line of Kauffmann et al. (2003). Right: areas encircled by the black contour line are classified as LINER-like within the log ([S   ii]  mathrmHα) diagnostic diagram using the LINER-Seyfert demarcation line of Kewley et al. (2006) and the extreme starburst line.