The type of butterfly on the cover of Learning MySQL is the blue spotted crow (euploea
midamus). One of more than 15,000 species of butterfly, this member of the brushfooted
family Nymphalidae (which also is home to the Monarch) is native to the Orient
and can be found in a region that spreads from Afghanistan to Australia. As its name
suggests, the crow is distinguished by its blue tint, as well as a series of white spots that
line the hind edge of its large wings.
In the course of their lives, butterflies go through four development stages: egg, larva,
pupa, and adult. Butterfly eggs, ovate or spherical in shape, are attached to leaves by a
powerful, quickly hardening glue until they hatch. In the larval stage, butterflies are
commonly referred to as caterpillars, and their bodies are divided into many small
segments, each possessing up to four pairs of legs. Caterpillars have insatiable appetites,
feeding practically nonstop on plant matter and molting approximately four or five
times before becoming pupae. At this third phase, the caterpillar becomes a chrysalis,
typically cleaving to the underside of a leaf. The chrysalis then consumes foodstuffs
that enable it to develop its wing structures and make the metamorphosis into an adult
butterfly. In this final stage of development, the butterfly is known as an imago, a fourwinged
creature with six legs. Imagos subsist mainly on flower nectar; some supplement
their diets with nutrients from sap, pollen, rotten fruit, or dung.
In Japanese culture, butterflies are somewhat paradoxically mythologized as both harbingers
of prosperity and impending doom. One superstition stipulates that a single
butterfly flying into one's bedroom presages the arrival of one's dearest love, while an
encounter with a swarm of butterflies is thought to be a precursor to ominous events.