At least this week's Atrophaneura species has one consistent name. The name is only occasionally a bit, well, gender-confused. Butterflies themselves are seldom gender-confused (though that can happen) but there is confusion about whether Latin adjectives, which agree with what they modify, should be used in masculine, feminine, or neuter forms. The Aurora Swallowtail is usually called Atrophaneura horishana but sometimes one finds Atrophaneura horishanus. Since horishana and horishanus aren't really Latin words, only the naturalists who registered them as species names for various lifeforms know what they mean or describe, so only those naturalists know what their grammatical gender in Latin ought to be. And they didn't tell us. These names were given to several different species and seem to have meant "found in eastern Asia." Horishan seems to have been the name of a neighborhood, though Google doesn't identify it as the current name of a place now. When scientists have quibbled about the name or classification of horishana, they've argued that it might be considered a sub-species of Atrophaneura nox.
Image donated to the Encyclopedia of Life by "irrubescens." As shown, the butterfly's hind wings are deeply scalloped but don't have real "tails." The color is determined by gender and affected by lighting. These butterflies can look black and bright red, or black and pink, or black and white. The black wing veins are constant whether the fore wings look black, blue, gray, brown, or white. The undersides of of the hind wings always have black dots on a background that may look red, pink, orange, or white. Females show black dots on the upper side of the hind wings too; males don't. The sides of the body are red; from below the head and abdomen look red, the legs and thorax black.
Same place, same species--different individual. From above the whole male butterfly can look blackish. The female's hind wings show her spots on a pink or white background above, pink or red below. The male's patches of black on red may look more vivid because of the solid dark color above..
They are found only in forests among the mountains, and are threatened by deforestation in the name of "development." An additional threat comes from the sale of butterfly carcasses for "collections." Butterfly bodies are like wild birds' feathers. They often drop at the feet of people who know where to look, gifts from Nature to those who might want to keep these souvenirs, but when people collect these pretty things they encourage idiots to go out and kill healthy animals. We should never pay for dead butterflies.
Museum specimens fade fast.
Getty Images, however, currently demands $500 for that site's best photo of a live horishana. Meh. We never have to pay that much for a picture, either. All the photos here are free for non-commercial use, though you would have to pay to use these pictures on things you intended to sell.
This video shows Atrophaneura horishana flitting and sipping in Taiwan, where they live. Like the other Atrophaneuras, they can move their fore and hind wings independently. As they sip nectar, their fore wings fan frantically while the hind wings are almost still.
The butterflies are not terribly rare; they are beloved emblems of Taiwan. As this video spells out more clearly, the Wo Xiong "butterfly valley" is a tourist attraction. People go out of their way to film, photograph, and draw these butterflies. Images of Atrophaneura horishana have been used on postage stamps, gifts, and souvenirs. Taiwan is proud of the diversity of butterfly and other wildlife species on the island, and encourages "ecotourism" with butterfly, frog, dragonfly, and other wildlife photo contests. That's why there are so many good clear pictures of living Atrophaneura horishana for everyone to collect.
Well, they are big showy tropical butterflies. The wingspan is typically about five inches, up to six and a half inches. Females are bigger than males, and more likely to have lighter-colored wings. In Taiwan, where the even bigger Birdwings are found, that's not considered gigantic (though it is about the size of North America's Giant Swallowtail), but it does catch the eye.
The butterflies normally fly only once a year, in July and August. They like flowers with lots of tiny florets. Taiwanese government writers aren't shy about encouraging visitors to snap their own shots of black-and-red butterflies fluttering above white and pale-colored flowers: https://www.trimt-nsa.gov.tw/htmlpage?code=2-1-3-12&culture=2 .
This female's colors, and the colors of the flower she's visiting, show why the species' main English nickname is "Aurora," colored like the dawn's early light. They're also called Highland Swallowtails and Red-Bellied Swallowtails. In the video above, where a butterfly flies toward the camera, the bright red underside of the abdominal section is especially prominent in contrast to the dark thorax..
This blue-white-and-pink color scheme is typical of the female of the species. This is a mother butterfly. She lays her eggs, which look like little yellow beads, by ones on either of two species of Aristolochia vines. The vines are inedible to most other animals and make the butterflies indigestible to most animals that try eating them.
The hatchling appears to be eating the shell from which it hatched. Caterpillars who do this usually continue to eat their cast-off skins as they grow and molt. Since they have a strong appetite for the skin of their own kind, they are likely to eat skins they didn't shed, too, and too bad if a sibling was living in the skin at the time.
The caterpillar is like several other young Atrophaneuras. The upper surface is textured to be hard for birds to bite into. Reddish and blackish pigments metabolized from the Aristolochia vines the caterpillar eats give the caterpillar a dark drab color rather than separating into clear pathes of color. A white belt stripe is clearly visible. The individual shown is feeling stressed, fully extending its osmeterium, which looks like the tongue of the snake the spots on its humped back suggest. The osmeterium releases a strong odor. To humans it smells fruity and not really unpleasant. To birds it seems unappetizing.
The color scheme seems designed to suggest a large unhealthy bird dropping. A caterpillar of this size can't really hide from birds so the next best thing is to look as nasty, relative to birds' taste, as possible.
The caterpillar doesn't need us to think it's pretty or nice, either.
The pupa literally hangs by a thread from the underside of a leaf, where it seems to benefit from a resemblance of a withered leaf.
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