The adult Broad-tailed Swallowtail butterfly can be seen:

Taiwan's national butterfly is the Broad-tailed Swallowtail butterfly. With its colorful hind wings and broad wingtails, it's quite a sight! But you can only spot it in one place--the sassafras forests of Taiwan. That's because the butterfly's larva (or caterpillar) feeds only on sassafras leaves. Unfortunately, sassafras forests are few in number and widely scattered in mountains. If they disappear, so will the Broad-tailed Swallowtail.
The adult Broad-tailed Swallowtail butterfly can be seen:
in spring only
from spring to fall
year-round
When the larvae change to pupae, they attach themselves to branches or tree trunks during the winter. Then adults emerge as butterflies between spring and summer, and can be seen through the middle of fall.
The wingspan of a Broad-tailed Swallowtail butterfly is about as wide as:
a cherry
a grapefruit
a lemon
From one tip to the other, the wingspan of this butterfly is about 10 centimeters, or 4 inches.
Its scientific name is Agehana maraho. Agehana is derived from Japanese Ageha, which means:
big wing
red spot
swallowtail butterfly
Ageha means swallowtail butterfly in Japanese language. Agehana is its form in Latin.
Large forests of sassafras trees grow throughout Taiwan.
Most sassafras forests grow at mid-altitude forests on mountains between 1,000 to 2,000 meters above sea level. They are located in central and northern Taiwan.
The caterpillars or larvae of the Broad-tailed Swallowtail butterfly are the same colors as the adult butterfly: red, black, and white.
The larvae are white, then turn greenish
before they transform into brown pupae (or chrysalises). Hanging on lower tree trunks, chrysalises look like dead twigs!
Scientific Name: Agehana maraho
Status: endangered
Range: Central and northern Taiwan
Habitat: mid-altitude sassafras forests
Host plant: Taiwan Sassafras
Appearance: hind wings with a distinct red, black,
and white pattern, and a broad tail
Wingspan: 9.5 to 10 centimeters (3.75 to 4 in)
Lifespan: 2 to 14 months
Discovery: in 1932 by a Japanese entomologist