Emission line maps of [N II] λ6584 (top left and bottom left), [O III] λ5007 (top right), and [S III] λ9069 (bottom right) for NGC 3242. In the top panels, the four knots are marked. The bottom high-contrast images show the new structures at the nebular shell (blue rectangles), while in the bottom-left, the four knots are marked as well (white rectangles). The color bar represent flux values (in units of ×10⁻²⁰ erg s⁻¹ cm⁻² spaxel⁻¹).