Appearance''Vanessa virginiensis'' is most easily distinguishable by its two large eyespots on the ventral side, whereas ''V. cardui'' has four small eyespots and ''V. annabella'' has none. ''V. virginiensis'' also uniquely features a white dot within the forewing subapical field, set in pink on the underside and usually also in the dorsal side's orange field.
The largest spot in the black forewing tips is white in ''V. cardui'', pale orange in this species, and orange in the West Coast species. The latter also has a purer orange background color of the dorsal side, as opposed to the darker and redder hue of the other two.
A less reliable indicator is the row of black eyespots on the dorsal submarginal hindwing. In the American Painted Lady, those on the opposite ends of the row are often larger and have blue "pupils". In ''V. annabella'', this applies to the inner two spots, while in ''V. cardui'' some of the black eyespots may have tiny blue pupils in the summer morph, but usually have none at all, and the eyespots themselves are all roughly the same size. The size of the wings are about 5 cm across.
Defense:''See'' Painted Lady
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