The aptly-named orchid mantis (Hymenopus coronatus) is actually the only insect known to imitate a plant as an offensive mechanism instead of a defensive one. Stick bugs and the like blend into the foliage in order to avoid predators; the orchid mantis uses its faux petals to ensnare prey of its own. Other animals hide themselves among foliage to accomplish the same feat, but the orchid mantis remains unique: It doesn't need to find a flower to hide in.
It's the whole flower.
Humans are quite easily fooled by this trickery -- in 1879, a journalist actually wrote about butterfly-devouring flowers he'd seen in Indonesia -- but scientists only recently found evidence that bugs are fooled as well. From National Geographic:
The team found that from the perspective of a pollinating insect, the color of orchid mantises is indistinguishable from a large number of Malaysian flower species.Next, the research team observed live orchid mantises in the field, counting the number of insects that were attracted to the mantis “flower.” They compared this to the number of insects that inspected an actual flower in the same amount of time.Their hypothesis was right: They were surprised to find the mantises actually attracted more insects than the real flowers.
Another interesting finding: The orchid mantis isn't actually mimicking any flower in particular. They just look like really big, pretty, generally welcoming flowers. To a bee brain, that's quite enough. And sometimes they're bright pink, which is somehow even better.