Head to head
Old World Swallowtail vs Eastern Tiger Swallowtail
Old World Swallowtail
VS Eastern Tiger Swallowtail
The Old World swallowtail and eastern tiger swallowtail are two large swallowtails in the genus Papilio, one on each side of the Atlantic, with very different patterns and caterpillar defences.
| Old World Swallowtail | Eastern Tiger Swallowtail | |
|---|---|---|
| Scientific name | Papilio machaon | Papilio glaucus |
| Wings | Yellow wings with black veins and borders, red and blue spots near the tail, and a short tail on each hindwing | Bold black and yellow tiger-striped wings with decoy tail-like extensions on the hindwings |
| Caterpillar defence | When threatened, pushes out a forked orange organ behind its head that gives off a strong smell | Young caterpillars look like bird droppings, and older ones develop large false eyes that resemble a small snake's head |
| Host plants | Plants of the carrot family, such as fennel and milk-parsley | Trees such as wild cherry and tulip tree |
| Range | Europe, Asia, and North Africa, with related forms in northern North America | Eastern North America |
| Habitat | Meadows, fens, and open country | Forests, woodland edges, and open habitat |
| Female forms | Not specifically documented | Females occur in two colour forms, one tiger-striped and one almost entirely dark |
| Conservation status | Least Concern, though the British form is rare and confined to the Norfolk Broads | Least Concern, with a stable population |
Old World Swallowtail vs Eastern Tiger Swallowtail: common questions
Which swallowtail caterpillar has a smelly horn?
The Old World swallowtail, which pushes out a forked orange organ that gives off a strong smell.
Which caterpillar looks like a bird dropping?
The young eastern tiger swallowtail caterpillar, which later develops false snake eyes.
Where do the Old World and eastern tiger swallowtails live?
The Old World swallowtail lives across Europe, Asia, and North Africa, while the eastern tiger swallowtail lives in eastern North America.