Spiny Devil Katydid: The Horned Leaf Mimic

A Spiny Devil Katydid in the Peruvian Amazon, 2021, sat unmoving on a branch, looking so much like a crumpled brown leaf with spikes and horns that a tree runner snake passed by without pausing. Enyptula spinosa’s armor isn’t just for show-its thorax bristles with orange-black thorns that drew blood from a field biologist running a finger along its back just to see if they were real. At dusk, the katydid let out a scratchy, rasping screech measured at 89 decibels, loud enough to startle an approaching tamarin monkey into leaping backward before it could snatch a meal. Its double-layered wings catch light the exact same way as the dried camu-camu leaves it favors, but not even the canopy’s sunlight makes its green eyes glint like other katydids. For years, entomologists found bitten remains but rarely living adults-and every time, the predators had abandoned the bodies untouched after the first mouthful. No bird, bat, or monkey has ever been recorded eating a healthy Spiny Devil Katydid to the end, because the spikes piercing the mouth and the bitter taste of its hemolymph combine into a defense that’s worked for millions of years.