The body of the Canthophorus dubius shieldbug is oval, black or dark blue, sometimes metallic green or bright violet, and can reach a length of 68 millimeters (0.240.31 inch) and a width of 3.54.5 millimeters (0.140.18 inch).
The body of these shieldbugs is oval, black or dark blue, sometimes metallic green or bright violet. Canthophorus dubius can reach a length of 68 millimetres (0.240.31 in) and a width of 3.54.5 millimetres (0.140.18 in). 
