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Blue Triangle Butterfly Information

Common to parts of Australia, South Asia and Southeast Asia, the Blue Triangle butterfly, or bluebottle, is a species of swallowtail. The different geographical locations across India, Myanmar, Sri Lanka, China, Taiwan, Indonesia, New Guinea and the Solomon Islands as well as Australia are home to roughly 15 subspecies of the Graphium sarpedon with brown or black-edged wings with a blue or turquoise triangular-shaped center.

Classification
- Class: Insecta
  Order: Lepidoptera
  Family: Papilionidae
  Genus: Graphium
  Species: sarpedon
  Common name: Blue Triangle (also known as bluebottle)
Egg and Caterpillar
- Blue Triangle butterflies lay their yellowish eggs one at a time on the upper sides of leaves, where they hatch into dark green spiny larvae. As the larvae develop into caterpillars, they are bright green with a white line near the head. They feed on the leaves, mainly from the laurel family. When they rest, they form a silk pad to rest on. The caterpillar's body tapers from head to tail and many of the subspecies have a yellow (or sometimes red) osmeterium---a sac in the first segment---that emits a pungent smell when the caterpillar is disturbed.
Pupae and Chrysalis
- The Blue Triangle's pupae are green and vein-patterned so that the pupae blends into the leaf background. Pupae attach on the underside of leaves of food plants and form a silk chrysalis from a single thread.
Butterfly Description
- Mature Blue Triangle butterflies have bright blue or turquoise wings with black or brown scalloped edges. The blue patterns join to make a triangle (hence the name) and the hind wings have four blue crescents near the trailing edge and red spots on the underside. Their wingspan is two and a half to three inches. Annually, two or more generations complete the life cycle.
Habitat
- The Blue Triangle butterfly's habitat in most regions is moist, low-level rain forest (below 5,000 feet) and monsoon forest, although some appear in suburban gardens. At these elevations, the butterflies fly just above the tree canopy. Some subspecies have adapted to higher elevations of the Himalayas and drier parts of Australia.
Behavior
- Blue Triangles display a powerful but erratic flight pattern. They rarely settle except to feed on flowers or drink from the moist sand along creek banks or pools of water. When feeding on flowers, they hold their wings vertically and the wings vibrate.
  
  The males appear to patrol the canopy and habitually feed in groups at the edge of roadside puddles. Sometimes they appear attracted to animal droppings, carcasses and rotting insects.

Insects & Science