In the vast and diverse world of insects, butterflies often capture attention with their intricate patterns and delicate flight. These winged creatures showcase an astonishing array of sizes, from the minuscule to the truly enormous. Among this incredible variety, one species stands out for its sheer scale, prompting curiosity about which butterfly holds the title of the world’s largest.
Unveiling the Largest Butterfly
The largest butterfly in the world is the Queen Alexandra’s Birdwing (Ornithoptera alexandrae). Females can reach a wingspan of up to 28 cm (11 inches), a body length of approximately 8 cm (3.1 inches), and a body mass of up to 12 grams (0.42 ounces), making them the heaviest known butterfly.
The Queen Alexandra’s Birdwing exhibits sexual dimorphism, with males and females looking distinctly different. Females have rounded, broad wings that are predominantly brown with cream or yellow chevron-like markings. Their bodies are cream-colored, with a small section of red fur on the brown thorax.
Males are smaller, with a typical wingspan ranging from 16 to 20 cm (6.3 to 8 inches), though some can reach up to 27 cm (10.6 inches). Their wings are more angular and feature iridescent blue-green hues with black markings, including a central black band. The abdomen of both sexes is bright yellow. The species was first discovered in 1906 by Albert Stewart Meek, a collector working for Walter Rothschild, who subsequently named it in honor of Queen Alexandra of Denmark.
Life in its Unique Habitat
The Queen Alexandra’s Birdwing is endemic to the Oro Province in eastern Papua New Guinea. It prefers tropical lowland rainforests, particularly the Popondetta Plain and the remote Managalas Plateau. It thrives in secondary and primary lowland rainforests up to 400 meters altitude on volcanic ash soils.
The butterfly’s life cycle is closely tied to its host plant, a type of pipevine. The larvae feed primarily on the leaves of Aristolochia schultzei. This plant contains aristolochic acids, which the caterpillars sequester, making them unpalatable to predators. Adult butterflies are strong fliers that inhabit the upper canopy, feeding on nectar from large flowers, such as Hibiscus species.
A Giant’s Fight for Survival
The Queen Alexandra’s Birdwing faces significant threats and is classified as endangered by the International Union for Conservation of Nature (IUCN). It is also listed on CITES Appendix I, prohibiting commercial international trade. Its limited distribution, with an estimated area of occupancy of only 128–140 square kilometers, makes it particularly vulnerable.
Habitat destruction is the primary threat to the Queen Alexandra’s Birdwing. Its rainforest home is being cleared for commercial logging, palm oil plantations, and agricultural development, including cocoa and rubber. Natural disasters, such as the 1951 eruption of Mount Lamington, also pose a risk by destroying habitat. Illegal collecting and black market trade also persist, though habitat loss remains the most pressing concern.