The prize for finest invertebrate mimicry goes to Hemeroplanes triptolemus for its convincing poisonous snake imitation! The snake mimic caterpillar, a Sphingidae moth, transforms into a mediocre moth in its larval stage. Because without a strong defense mechanism, sphinx moth caterpillars are nothing more than energy-dense ‘nom-nuggets’ for the jungle’s predators.
Instead, the larva swells and reveals its underside to resemble a snake’s head with black eyes and light reflections.
But it’s not easy. The caterpillar starts its protective move by reversing and twisting its body, revealing its yellow, white, and black underside. Inhale via small openings on its sides (spiracles) and pump it to the front. After the segments are expanding, the caterpillar morphs into a poisonous snake with a diamond-shaped “face” and huge, black eyes.
If the “deadly” (and expensive) outfit isn’t enough to scare a predator, the caterpillar may also attack like a snake.
For whatever reason, the snake mimic caterpillar has a false face on the same end as the real one.
“Deflection may not function effectively for a caterpillar since an assailant may penetrate or pull off any section of its body,” says eyespot specialist Dr. Thomas Hossie. “This defense is used to scare or startle an assailant, so they flee (or fly) rather than risk a deadly snake encounter.”
We also know of a moth that can disguise itself as a snake in its adult form, but this disguise costs a lot of energy.