Солтүстік Америкалық қара көжантұзды көбелек

Species of insect

Papilio polyxenes, the (eastern) black swallowtail, American swallowtail or parsnip swallowtail, is a butterfly found throughout much of North America. An extremely similar appearing species, Papilio joanae, occurs in the Ozark Mountains region, but it appears to be closely related to Papilio machaon, rather than P. polyxenes. The species is named after the figure in Greek mythology, Polyxena (pron. : /pəˈlɪksɨnə/; Greek: Πολυξένη), who was the youngest daughter of King Priam of Troy. Its caterpillar is called the parsley worm because the caterpillar feeds on parsley. P. polyxenes is part of the genus Papilio, which is the biggest group of the family Papilionidae. Subspecies polyxenes, once found in Cuba, is now considered likely extinct. Members of this genus typically feed on plants of the family Lauraceae, Rutaceae and Umbelliferae. They are usually found in open areas like fields, parks, marshes or deserts, and they prefer tropical or temperate habitats.

Eggs are pale yellow. Young larvae are mostly black and white with a saddle, and older larvae are green with black transverse bands containing yellow spots.

This caterpillar absorbs toxins from the host plants, and therefore tastes poor to bird predators. A section of the green pupae will turn a much darker green at the very end of the pupae stage. This color change occurs a few hours to a full day before hatching.

The black swallowtail has a wingspan of 6.9–8.4 cm, and females are typically larger than males. Both sexes show a red spot with a black bullseye on the inner hind margin of the hindwings and an isolated yellow spot on the front edge of the wings. The ventral side of wings of males and females are essentially identical: forewings have two rows of pale yellow spots, and hindwings have rows of bright orange spots separated by areas of powdery blue. The ventral side also acts as an effective mimic for both males and females for protection against predators.

Females lay single eggs on host plants, usually on the new foliage and occasionally on flowers. The eggs stage lasts 4–9 days, the larval stage 10–30 days, and the pupal stage 18 days. Feeny et al., 1985 finds that survival of eggs and larvae of P. polyxenes varies depending on the location (near Ithaca, New York) where the eggs were laid. Eggs laid on wild carrot or parsnip plants were more likely to survive to the fifth instar than were eggs laid on poison hemlock. Eggs laid on plants at elevations of above sea level were more likely to survive than eggs laid at 120 meters above sea level. There were also significant differences in survival rates between early and late broods in a year, and between years. In all cases, the primary cause of mortality was predation.

Winter is spent in the chrysalis stage, and adults will emerge in the spring to seek out host plants. Adults will emerge in the mornings on a daily basis. First brood adults will fly from mid May until late June, second brood adults will fly from early July until late August, and occasionally a partial third brood will occur that will emerge later in the season.

Male butterflies secure territories to use in mate location and courtship. Male territories are generally of high relative elevation and topographic distinctness. This feature serves as an advantage to the lek mating system described later, as males will be concentrated in predictable locations and will be easy to encounter by females.

This type of territorial organization leads the black swallowtail to engage in a lek mating system. The territory that has the most male male encounters can be seen as being the most desirable to both males and females, and is also the territory that has the highest female visitation rate.