MNN Galleries

15 amazingly deceptive caterpillars

By: Anna Norris on Jan. 15, 2014, 3:20 p.m.
Black swallowtail caterpillar showing osmeterium

Photo: Wikimedia Commons

10 of 17

Black swallowtail caterpillars

Swallowtail butterfly caterpillars like the black swallowtail larva shown here sport a special organ that extrudes whenever they feel threatened. Called an osmeterium, this V-shaped "tongue" of sorts can send out strong odors — so if a predator isn't already spooked by the sudden appearance of devilish horns, it will certainly be turned off by the smell.