Swallowtail butterflies belong to the Papilionidae family and encompass over 550 individual species. They can be found on every continent in the world but they are most common in warm regions like the tropics. The largest butterfly in the world, the birdwing, is a swallowtail.
A swallowtail butterfly has unique bottom wings that are forked, especially visible when it is still with spread wings, and is the reason for the name.
There are three subfamilies of swallowtail:
Braoniinae
These swallowtails are only found in Mexico. These were once common in a variety of regions but over time have become secluded to one small Mexican region.
Parnassiinae
The species in this subfamily are common to mountainous areas but can be found in deserts, forests and grasslands as well. They typically have small red dots on their hindwings.
Praepapilioninae
The final subfamily is comprised of only one genus (Praepapilio) which two extinct species.
Swallowtail caterpillars eat a huge range of plants but an interesting note is that some of their favorite foods are actually toxic. By eating toxic plants, the swallowtail caterpillar and butterfly become toxic as well which helps keep them safe from predators.
Another useful tactics against predators is the swallowtail butterfly’s ability to take on the appearance of plants predators do not like. This trait isn’t found in all species.
Some swallowtails are considered pests by humans based on what plants they eat. In particular, some species enjoy citrus plants which can be bothersome to those growing them for crops.