Papilionidae Butterfly Family
The family Papilionidae is a remarkable family of some of the largest butterflies in the world.
The family Papiliondae contains around 550 species of butterflies including Swallowtails, Apollos and Birdwings. Swallowtails (Papilio glaucas), are large and very colourful butterflies found on all continents except the Antarctica.
Within this particular family there are some of the largest butterflies in the world which are best known as the Birdwing butterflies from Australia.
Swallowtail Butterflies are strong fliers with distinctive yellow and black striped markings on their wings and body. The lower wings have a curved band of blue ending in a small red spot. They have a wingspan of 3.5 – 6.5 inches (9 – 16.5 centimetres). Adult Swallowtails have long tails which resemble those of the Swallow Bird, in which it is aptly named.
The Swallowtail is the largest butterfly in Britain, and also one of the most beautiful. There are around 225 species of swallowtails. They inhabit mainly marshlands and in Britain, the caterpillars feed only on milk parsley.
Swallowtail butterflies differ from all other butterflies as their caterpillars have a unique organ behind their heads. This organ is called the ‘osmeterium’. The organ is a forked structure which can appear like retractable horns and are normally hidden unless the caterpillar is threatened.
When the caterpillar is posed with a threat, it emits a smelly secretion containing terpenes (a class of hydrogen and carbon) to deter its predators.
Swallowtail butterflies, being large, colourful and attractive, have been the target of butterfly collectors for many years.
In the USA, the Oregon Swallowtail Butterfly is the state insect of Oregon, the eastern tiger swallowtail is the state insect of Virginia, Georgia, Alabama, South Carolina and Delaware.
Species of Swallowtails include:
Anise swallowtail (Papilio zelicaon), Black swallowtail (Papilio polyxenes), Eastern tiger swallowtail (Papilio glaucus), Pipevine swallowtail (Battus philenor), Scarce swallowtail (Iphiclides podalirius), Spicebush swallowtail (Papilio troilus), Western Tiger swallowtail (Papilio rutulus), Old World Swallowtail (Papilio machaon) and the Citrus swallowtail (Papilio demodocus).
The Apollo Butterflies (Parnassius apollo) are a distinctive group and all species are alpine and capable of living at high altitudes. Most species have two small reddish spots on their hind wings. They are found throughout Europe and into central Asia. They inhabit mountain meadows and pastures, up to 2,000 metres above sea level.
The Apollo is a beautiful white butterfly with shiny wings. Their wings have slightly transparent edges and there are a number of large black spots on the forewings. Adults can be seen flying during mid-summer. These butterflies are mountain-dwellers and it is thought that the species became widespread during glaciating periods.
The caterpillars are velvety black with orange-red spots along the sides. These caterpillars feed on stonecrop and houseleek. When the caterpillar is fully-grown it will pupate in debris on the ground, forming a loose cocoon from which the adult butterfly emerges following metamorphosis. The pupae are typically attached to the substrate attached by the cremaster (a hook-shaped protuberance from the rear of the chrysalis casing) but with head up held by a silk girdle.
The population of the Apollo butterfly has been declining throughout its range due to a combination of habitat destruction, over collection, air pollution, caterpillar parasites, predation and competition with other species that feed on the caterpillar food plants.
Birdwing Butterflies are large, tropical butterflies native to mainland and archipelago Southeast Asia and Australasia (with one Indian species). Birdwings are named for their exceptional size, angular wings and birdlike flight. Included among the birdwings are some of the largest butterflies in the world.
A well-known species is Rajah Brooke’s Birdwing (Trogonoptera brookiana) pictured left.
Birdwings have a maximum body length of 7.6 centimetres (3 inches) and a wingspan of 28 centimetres (11 inches). They have showy colouration in contrasting shades of green, yellow, black, white and sometimes blue or orange. They are slender and the hind wings lack tails. Females are larger and less colourful than males.
Males and females of most birdwings are similar and have jet black to brown dorsal forewings, often with the veins bordered in grey to creamy-white. Their thermo receptors are sensitive to sudden increases in temperature and they are thought to help the butterfly thermo regulate and avoid overheating while basking.
Birdwings inhabit rainforests and adults are usually observed along the forest periphery. They feed upon and are important long range pollinators of nectar-bearing flowers of the forest canopy, as well as terrestrial flowers, such as lantana (a genus of about 150 species of perennial flowering plants, native to tropical regions of the Americas and Africa). They are strong flyers and seek sunlit spots in which to bask.
Breeding behaviour varies little between species. The females role is relatively passive, slowly fluttering from perch to perch while the male performs an elaborate, quivering yet stationary dance 20 – 50 centimetres above her. After mating, females immediately begin to seek appropriate host plants. The female lays her spherical eggs under the tips of the vines leaves, one egg per leaf.
The caterpillars are large eaters but move very little. A small group will devour an entire vine. If starved due to overcrowding, the caterpillars may resort to cannibalism. Fleshy spine-like tubercles line the caterpillars backs, and their bodies are dark red to brown. Some species have a retractable organ behind their heads called an ‘osmeterium’. Shaped like the forked tongue of a snake, the osmeterium excretes a smelly secretion and is emitted when the caterpillar is threatened.
Birdwing pupae are camouflaged to look like a dead leaf or twig. Before pupating, the caterpillars may wander long distances from their host plants. It takes four months to get from egg to adult. Apart from predation, this species can also survive up to three months as an adult.