A Predator in Petal's Clothing
In the humid rainforests of Malaysia, the orchid mantis (Hymenopus coronatus) is a lethal predator. This insect uses aggressive mimicry, a strategy where a predator imitates a harmless species or object to lure prey. Its four walking legs are flattened with lobes that look like flower petals, and its body is pink and white, a color scheme that can change to match its background. Field studies confirm this deception is remarkably effective. A solitary orchid mantis attracts more pollinators, such as bees and flies, than many actual flowers in its vicinity.
The mantis's allure is so powerful because it is a supernormal stimulus. It mimics no specific flower, but instead presents a generalized, irresistible collection of floral cues. Spectrometer analysis shows that the mantis's color is indistinguishable from local flowers from the perspective of a hymenopteran pollinator's vision. This visual trickery is so complete that the mantis can hunt successfully even when sitting on green leaves, far from any real blossom. Some research also suggests juvenile mantises employ chemical mimicry, emitting compounds like 3-hydroxyoctanoic acid (3HOA) to attract honeybees.
A Life of Deception
This floral deception is primarily the domain of the female mantis. She exhibits extreme sexual dimorphism, often growing to more than double the size of the male. Her larger body and more pronounced floral features are evolutionary adaptations driven by predatory selection; a bigger lure can attract and subdue larger prey like butterflies, providing the necessary resources for egg production. The male, by contrast, is smaller and less colorful, built more for camouflage and agility to find mates while avoiding predators.
The deception begins early in life. First-stage nymphs are not pink and white, but a striking black and red. This coloration is a form of Batesian mimicry, where the harmless nymph imitates a foul-tasting, well-defended species of stink bug to deter predators. After its first molt, the mantis undergoes a dramatic color shift to its characteristic floral pattern, a change regulated by the hormone ecdysone and a specific pigment transporter gene. As an adult, the female becomes a lethal sit-and-wait predator, often swaying gently to mimic a flower in a breeze before striking prey with its toothed front legs.