Bug FAQSpangle Swallowtail
Papilio protenor · Order: Lepidoptera · Family: Papilionidae
The spangle swallowtail is a large butterfly with indigo-blue black upper wings and distinctive pale streaks and a red-marked tornal angle. It occurs across South-East Asia, from northern Pakistan and the Himalayas through China, Korea, Japan and Southeast Asian countries.
Source: Wikipedia
How to recognize it
Upperside is velvety indigo-blue black, darker on the forewing; pale streaks run along the veins and a broad pale yellow-white streak appears on the hindwing with bluish-scaled interspaces and a red tornal angle. Underside shows dull black forewing with broad grey streaks, while the hindwing matches the upperside but adds a large irregular tornal patch, pinkish-red subterminal lunules, and blue-scaled irrorations in several interspaces.
Source: Wikipedia
Size
Papilio protenor is a large butterfly.
Source: Wikipedia
Where it lives
Females show a strong preference for the citrus plant Citrus unshiu as a host. Males tend to stay in the same area more than females.
Source: Wikipedia
What it eats
The caterpillars feed on Zanthoxylum alatum, a rutaceous plant related to citrus. Overall the species is a specialist on citrus family plants.
Source: Wikipedia
Life cycle
Pupae may resemble rough bark or be uniformly green.
Source: Wikipedia
Where it comes from
It is native to parts of South-East Asia including northern Pakistan, the Himalayas, Bangladesh, Burma, southern China, Vietnam, Laos, Taiwan, both Koreas, Japan and Nepal.
Source: Wikipedia
More photos
Questions people ask
Which plants do spangle swallowtail larvae eat?
They feed on Zanthoxylum alatum, a citrus-related plant.
Source: Wikipedia
Where can I find spangle swallowtails?
They occur in South-East Asian regions such as northern Pakistan, the Himalayas, Bangladesh, Burma, southern China, Vietnam, Laos, Taiwan, Korea, Japan and Nepal.
Source: Wikipedia
How can I recognize an adult spangle swallowtail?
Look for a large butterfly with indigo-blue black upper wings, pale streaks, a broad pale yellow-white streak on the hindwing, bluish-scaled interspaces and a red-marked tornal angle.
Source: Wikipedia
Same family (Papilionidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Papilio_protenor
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.