This Tiny Spider Turned Its Back On Bugs And Lives Off Acacia Leaves

In a remarkable break from the carnivorous norm, scientists have discovered a rare vegetarian spider that prefers leaves over live prey. The jumping spider Bagheera kiplingi, native to Central America, is the first known spider species to rely primarily on plants as its food source.

Rather than catching insects in webs, these tiny arachnids – about the size of a pinky nail – delicately munch on nutrient-rich tips of acacia leaves. They’ve evolved cunning strategies to sneak past the aggressive ants that protect these plants in exchange for nectar and shelter. Using stealth, quick direction changes, and silk lifelines, the spiders dodge the ants to reach their plant-based meals. Research shows this unique diet isn’t a fluke.

In Mexico, about 90% of the spiders’ nutrition comes from acacia plants, while Costa Rican populations get roughly 60% of their food from the same source. Despite occasionally supplementing their diet with ant larvae or nectar, B. kiplingi spends its entire life on these shrubs, carefully avoiding ant patrols and nesting where the guardians are least active.

Their behavior turns traditional spider biology on its head, as most reference texts have long dismissed the idea of herbivorous spiders. As one researcher put it, finding a vegetarian spider is “on par with the flying pig in terms of novelty.”