@ficopedia: Technically as an ecologist I should be calling them 'ladybird beetles'.
The reason we don't call them ladybugs is that there is a group of insects known as 'true bugs' which include things such as bed bugs, shield bugs, aphids, water scorpions, water striders, assassin bugs and cicadas, all unified by the fact that they have piercing mouthparts and go through incomplete metamorphosis. Ladybirds go through complete metamorphosis and have chewing mandibles, thus making them beetles and are not bugs.
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