Male Black Swallowtail on a zinnia flower. The upper row of large yellow dots is a distinctive feature of the males.
Another male Black Swallowtail, nectaring on butterfly weed (orange milkweed). Black Swallowtails are common and widespread from April through October.
This is a female Black Swallowtail. The upper row of yellow dots is not as large as in the males, and females have more blue at the base of their wings.
Another female Black Swallowtail nectaring on echinacea at Huffman Prairie.