Ladies and gentlemen, the award for best invertebrate mimicry goes to Hemeroplanes triptolemus for its masterful impersonation of a venomous snake!
Native to the rainforests of the Amazon, the snake mimic caterpillar transforms into a rather unimpressive moth in the Sphingidae family. However, in its larval stage, it uses an astonishing survival tactic. This is crucial because, without a good defense system, sphinx moth caterpillars are essentially energy-rich snacks for the jungle’s predators.
To avoid this fate, the larva of this moth expands and exposes its underside to mimic a snake’s head, complete with black eyes and light reflections.
The caterpillar begins its defensive maneuver by throwing itself backwards and twisting its body to reveal hidden shades of yellow, white, and black on its underbelly. Then, it inhales air through tiny holes in its sides (known as spiracles) and pumps it to the front of its body. Once the segments are inflated, the caterpillar is truly transformed, taking on the form of a venomous snake with a diamond-shaped “face” and large, black eyes.
If this “deadly” and energy-intensive costume isn’t enough to deter a predator, such as a lizard or a bird, the caterpillar might also strike like a snake to enhance the effect.
While deflection—using eyespots to draw predators’ attention away from the head—is common among animals, the snake mimic caterpillar’s false face is actually located on the same end as its real one.
“Deflection might not work well for a caterpillar because the caterpillar probably won’t survive if any part of its body gets pierced or ripped off by an attacker,” explains eyespot expert Dr. Thomas Hossie. “This defense is all about intimidating or startling an attacker who will run (or fly) away instead of risking a lethal encounter with a snake.”
Interestingly, there is also a moth that camouflages as a snake in its fully developed stage, but this disguise is also quite energy-intensive.
However, the snake mimic caterpillar seems to beat everyone else in the animal kingdom when it comes to sporting the best snake costume ever.
