The oyster butterfly (Phyciodes nacre) has a short life cycle, usually dying shortly after its pupal stage. It is incapable of defending itself against predators, but has none, as it is inedible. It dies usually because its mobility is restricted by its own physiological eccentricities.
Anyone who studied butterflies in grade school might have visions of hard egg cartons painted green, or poster painted newspaper filled tights, but the larval and pupal stages are drastically different. While a Monarch butterfly might climb a tree, make enough silk to stick to a branch, and then molt into the final hardened chrysalis shell, an oyster butterfly has a much more complicated process.
Although the egg stage is identical, everything afterward is entirely unique. The egg transitions into a larval form, somewhere between a slug and a caterpillar. The larva is most formally called the veligerpillar.
It spends most of this phase crawling along the earth, ambulating via its giant foot-body, searching for perfect grains of sand. When it finds one, it absorbs it into its body, storing it in its collection for later. When the veligerpillar has collected five grains of sand, it is ready to transition into the “pupa-spat” phase.
In this phase the veligerpillar sticks itself to the underside of a ground-level leaf or vine, often in a cool, heavily forested area to support the creature’s moist foot-body. It molts its last layer of filmy skin and reveals its underlying hardened exoskeleton. The chrysalis resembles a thin, flaky, soft oyster shell.
Inside of this chrysalis the veligerpillar body dissolves and reforms around the grains of sand. It begins with the two smallest, forming the butterfly’s future eyes. The other three grains become the head, thorax, and abdomen. Eventually gravity pulls the hard-packed pearlescent body out of the thin abalone flakes of the chrysalis, ending the metamorphosis, and the butterfly falls to the ground with an impossibly silent thud.
It expands its wings with its first breath of outside air, but is unable to fly. The weight of its body is too heavy to be supported by its wings, but they are magnificent. Light filtered through whatever leaves are overhead reflects off of the silver-rainbows of the pearl wings. Invisible insects accustomed to the dark world of low vegetation are attracted to the sparkling, glimmering constellations projected onto the underside of the leafy sky. Eventually, whether blinded or drawn, the specks fall toward the source, and the butterfly sucks whatever sustenance it can get from these passive victims.
The oyster butterfly spends its short life crawling on the ground or onto stems and leaves, feeding on what specks of insect it can catch through this trick of the light until its ultimate demise. It has few predators, given the impossibility of chewing or digesting its body, but the butterfly’s inability to fly more than a hop or two, and general high visibility due to its mirrored wings, render it prone to harm.
Often the veligerpillar never exits its shell-chrysalis. These creatures die only partially formed, and appear to be oysters with pearls inside. They may be found in heavily forested areas under fern fronds or even under mossy logs.
There are unsubstantiated reports of oyster butterflies taking flight, but the details are scant. Scientists theorize that these rare specimen select the perfect combination of sand to yield a perfect proportion between body and wing. No one knows what light show awaits the person fortunate enough to see an oyster butterfly that opens its wings and takes off into the sunlight.