From Nookipedia, the Animal Crossing wiki
Not to be confused with the Spotted Ladybug.
The Ladybug (テントウムシ, Tentōmushi), is a small, black and red insect that appears throughout spring and summer. They are common and worth 200 bells. They can also been seen in October. Ladybugs crawl on any sort of flower, appearing as a red spot on them (which makes it hard to find them on red flowers). They will fly away if players approach them too quickly or walk onto the flower they are crawling on. Their buzzing when they fly is quiet.
Donating to the museum
In Animal Crossing
Blathers, the curator of the museum, says the following when it is handed to him for donation:
"Ladybugs are one insect I thought might appeal to me. Then I made the grievous error of touching one. This vile fluid appeared from someplace and.. Oh, it was everywhere! Blech! Utterly appalling!"
The Spotted Ladybug can be found nestled among the flowers in the center of the insect room after donation.
In Wild World
When donated, this is what Blathers says:
"I've heard it said that ladybugs are "so cute!" Sadly, I must disagree. I touched one once, and this vile yellow fluid... Blech! I shan't discuss it... Hoo.. If that's "cute," then I weep for the world!"
After donation the Ladybug appears in the museums first insect room, on the left side, on the flowers between the palm trees.
In City Folk
The following information is what Blathers says to the player upon donation of the Ladybug:
"Mad as it sounds, I find a lone ladybug quite fetching... But they tend to cluster in cold weather. If you were to flip over a rock in winter, you might see the underside crawling with them... Such vileness! Bleeeech! The very thought gives me the quivers!""
After donation, the Ladybug can be found sitting on a flower on the lower terrace of the insect room.
In "New Leaf"
Upon being donated, the Ladybug can be found in the first room of the bug exhibit, on the red flower on the right side.
"Despite the name, not all ladybugs are "ladies". There are also male ladybugs. Though you'll see different ladybugs with different numbers of spots, they don't get more as they age. Ladybugs eat insects harmful to crops. A few species eat the leaves of crops, but most are beneficial. They're tough against the cold, but during winter they stay in groups under dry leaves for warmth."
Frequently referred as a "ladybug" in the U.S. or a "ladybird" in Britain, ladybird beetles contain 5,000 species of Coccinellidae, worldwide. Species can vary from number of spots to body shape, and even color. In fact, tan varieties of ladybird beetles exist. The ladybird beetle represented in the Animal Crossing series series is Coccinella septempunctata, the Seven-spot ladybird beetle. It lives almost anywhere where there are aphids, its main prey, to eat. Ladybird beetles are considered by many to be beneficial to plants due to their eating habits- aphids themselves eat plants, so by introducing ladybird beetles, plants can be protected. The seven-spot itself was introduced to North America in this manner.
The yellow fluid that Blathers refers to is called reflex blood; the ladybird beetle breaks its own joints to induce this bleeding. The blood has an unpleasant odor which keeps predators at bay if the warning colors do not suffice.
Ladybird beetles can lay several dozen eggs, which hatch after a period of three to four days. A number of infertile eggs are also released by ladybird beetles in order to provide food for their young - when food is scarce, the number of infertile eggs is much greater than the number of fertile ones.
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