Caterpillar: variable coloration. Body and spines yellow to black. Eight silver spots on back. (1)
Adult: underside of hindwing has unique silver "question mark" shape. Upper forewing has extra black dash not in the similar Eastern Comma. (2) Upper hindwing of summer form is mostly black with short tails; winter form is orange/black with longer violet tipped tails. (1) Wing are very angular in outline.
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