About Papilio ornythion Boisduval, 1836
Papilio ornythion, commonly known as the ornythion swallowtail, is a swallowtail butterfly belonging to the subfamily Papilioninae. Its confirmed range includes Mexico and Guatemala. It is occasionally recorded in central and southern Texas and New Mexico, and is rarely sighted in southern Arizona and Kansas. The wingspan of this species measures 83 to 115 millimetres, which equals 3.3 to 4.5 inches. On the upper (obverse) surface of the wings, the base color is black, crossed by a pale yellow band that is divided by black veins. A small number of additional pale yellow spots are present above the wing cell and in the submarginal area of the forewings. The hindwings have a pale yellow stripe that aligns with the forewing band, plus a series of submarginal pale yellow spots. In the anal angle of the hindwing, there is an orange crescent-shaped mark, topped by an iridescent blue crescent mark. The hindwings end in elongated black tails. On the lower (reverse) surface of the wings, pale yellow is the dominant color. The forewings follow a similar pattern to the upper surface, but the black areas are striped with yellow. The hindwings are pale yellow with a black border, and have a row of black-edged orange crescent marks across their middle section. Females of this species occur in two distinct forms: one that matches the appearance of the male, and a dark morph. In the dark female form, the median band on the upper surface of both the forewings and hindwings is absent. The lower surface of the wings is mostly black, with pale yellow submarginal spots on the hindwings in addition to the median orange crescent marks. The upper side of the body is patterned with pale yellow and black; the dark female form has a darker body overall. Adult ornythion swallowtails are active from April to September, and there are thought to be two generations each year. The larvae feed on the leaves of Citrus trees, while adult butterflies feed on flower nectar.
