Invertebrates
Orchid Mantis
Hymenopus coronatus · also called orchid mantis, walking flower mantis, pink orchid mantis
The orchid mantis is a small ambush predator from the rainforests of Southeast Asia that has evolved to look like a flower — not to hide among flowers, but to be the flower that bees and butterflies fly toward. It is one of the best-studied examples of an animal using beauty as a trap.
Overview
Orchid mantises live in lowland tropical rainforest across Malaysia, Indonesia, Thailand, and nearby countries. The conspicuous adult is the female, a pink-and-white insect about the length of a thumb with four petal-shaped legs and a habit of rocking gently as if stirred by a breeze. She typically perches on green foliage or a stem, in the open, waiting.
Being the flower
For a long time the orchid mantis was assumed to be a camouflage specialist, hiding inside blossoms. Careful fieldwork overturned that. The mantis works without any flower present: its own body supplies the colour, size, and ultraviolet signal that pollinating insects read as a food source, and experiments found that bees and flies approached a solitary mantis more readily than they approached a real flower. This is aggressive mimicry of flowers as a general category — a strategy not clearly documented in any other animal. When a pollinator lands or hovers close, the mantis strikes with its spined forelegs.
A disguise that develops
The mimicry is not present from hatching. Newly emerged nymphs are red and black, resembling a foul-tasting assassin bug that predators leave alone. After the first moult they turn floral, gaining the petal lobes and the sway, and can adjust their shade between white and pink over a few days to suit the local light and vegetation. Adult females keep the flower form for life; the much smaller males are plain by comparison.
Extreme size difference
Female orchid mantises reach 6–7 cm; males are often under 3 cm. The large female makes a more convincing and more profitable “flower” and can capture big pollinators such as carpenter bees, while the small male matures quickly on little food and moves easily to find mates — though he must approach the predatory female with care.
Status
The orchid mantis has not been formally assessed for conservation. It is locally common in intact forest and is heavily traded in the exotic-pet hobby, where captive-bred nymphs are readily available and preferred over wild-caught animals.
Orchid Mantis: common questions
Does the orchid mantis hide inside orchids?
No — that is the common misconception. The orchid mantis usually sits on green leaves or bare stems, not on flowers, and it does not need a flower nearby to work. Its body itself is the lure. Field experiments in Malaysia showed that pollinating insects flying past were actually more likely to approach a lone orchid mantis than to approach a real flower of similar size, because the mantis presents an especially strong version of the visual signal — the right colour, the right size, and a UV pattern — that says "nectar here." This makes it the clearest known case of an animal using aggressive mimicry of a flower in general, rather than copying one particular plant.
Why are female and male orchid mantises so different in size?
The female is around 6 to 7 centimetres long; the male is often under 3. This is one of the most extreme cases of sexual size difference among mantises. The large female is the one doing the flower mimicry and prey capture — a bigger body makes a more convincing and more rewarding "flower" and lets her tackle large pollinators like carpenter bees. The small, slender male matures faster, needs less food, and is more mobile for finding mates. He also has to approach the much larger, predatory female carefully to avoid being eaten.
How does the disguise change as the mantis grows?
It starts life not as a flower but as a warning. Freshly hatched nymphs are boldly patterned in red and black, closely resembling a species of assassin bug that predators avoid. After the first moult the nymph turns white and pink and takes on the petal-lobed legs and the swaying posture of the flower mimic, and it can then fine-tune its shade between white and pink over several days depending on the background and lighting. Adult females keep the floral form; the tiny adult males are plainer.
Can you keep an orchid mantis as a pet?
They are one of the most popular mantises in the exotic invertebrate hobby, and captive-bred nymphs are widely available. They are, however, considered fairly demanding — they need high humidity, warmth, live flying insects as food, and careful handling of the big female with the small male at breeding time. Because the species has not been assessed for conservation status and is collected from the wild in some areas, buyers are encouraged to choose captive-bred stock.