This week's butterfly is Atrophaneura semperi, a large tropical swallowtail found primarily in the Philippines. It is considered to be one species that has at ;east tem different-looking subspecies; individuals don't all look just alike. Butterflies now regarded as subspecies of semperi have been classified as at least three additional species. Unlike many wild animals in which the female is better camouflaged than the male, both sexes of semperi show a warning coloration strategy in which the female is probably more conspicuous than the male, and only the females of some subspecies show a consistent difference in wing coloration. The hind wings may have distinct, sometimes club-shaped "swallow tails" or only vestigial "tails"; they may show conspicuous red spots, or faint pink spots, or no sots at all on the upper side. Males are more likely to look black or iridescent with bright red spots, females dark brown or gray with faded pink spots. Females' hind wings are more likely to show more conspicuous and variable spots, while males are more likely to develop impressive scent folds that release an odor even humans notice and dislike. Like several of the Atrophaneuras they can look all black, or black and white, from above and show red only from below. They are large butterflies, the wingspan typically 5 to 6 inches.
Photo by Taipingling.
Sebastian Brjoveanu posted a short GIF-style video in which a male and female semperi perch on a man's fingers and flutter over his hand, showing their black-and-white upper surfaces and then their red undersides. The bright red below may suggest the idea that the butterflies bathed in the man's blood, but the video clearly shows that they don't. They get their red coloring from the Aristolochia they ate as caterpillars; some at least start out very bright, and some show pink or white rather than red.
Photo by stijn_de_win.
Instead of being named after a character in literature, semperi was named after Charles Semper, onr of the first naturalists to write about the species. (As a Latin word semper means "always"; as a family name Semper has been traced to ancestors who lived near St Pierre's church.) It has been given two English names: the Black Ballerina, and the Blood-Red Vampire. Not that anyone ever seriously thought the "Vampire Butterfly" bit anyone. It doesn't; it can't. If anything the Atrophaneuras are less likely than some other butterflies are to annoy wounded people by licking fresh blood from a wound. Most male swallowtails do some composting, reprocessing the mineral salts found in carrion and polluted water; most of the Atrophaneuras are thought to be strictly pollinators. But the red spots on the undersides of its black wings reminded someone of Dracula's cloak.
Photo By Stefan Schneider - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=33177400 . The suggestion of a dancer's white tights comes from scent folds, a feature several male Atrophaneuras share.
Some prefer to call semperi simply the Batwing, which is a general nickname for all the Atrophaneuras, as if it were the most important or interesting species in the family. And although the English name "Black Swallowtail" is associated with species that have more colorful wings, some semperi really qualify to be described as black swallowtails:
Atrophaneura semperi is neither really common nor believed to be endangered at the moment, so, although it's well documented on the Internet, many of the web pages about this butterfly are store sites offering dead bodies for sale. As regular readers know by now, the position of this web site is that we should never pay for dead butterflies or parts of them. People used to think they had to live with boxes full of decomposing bodies to learn new information about butterflies. Now we can "collect" butterflies with a camera, which makes collections much easier to keep, study, share, enjoy, and leave to our schools in our wills.
Some of the subspecies that have evolved on different islands are more threatened than others, though. The subspecies aphthonia, one of those that used to be accepted as a distinct species, is considered endangered by habitat loss. All of these butterflies' habitat is in deep tropical forest, although different subspecies favor different flowers and some have survived in the second-growth stage when forests were not completely clear-cut.
They have been called "the type species for the genus," the most typical species of Atrophaneura (this is one Atropaneura that has not been reclassified and given a different genus name). Adults fly for about two weeks, during which time females lay eggs by ones on Aristolochia leaves.
The caterpillar has been described as purplish brown with red tubercles., a typical Atrophaneura that eats vines in the genus Aristolochia.
The pupa is yellowish brown and appears well camouflaged as a dead leaf. The emerging butterfly sometimes drips bright red pigment onto and below the pupal shell. This is not blood. Butterflies' blood is colorless. However, many red and orange butterflies store more red pigment, as caterpillars, than their adult color pattern really needs. During eclosion (emergence from the chrysalis) they excrete surplus pigment as what is technically known as meconium.
Familiar though these butterflies are, I didn't find photos of their early stages.
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