Ant lions are ferocious predators, but some of them don’t have a mouth.
At least not in the usual sense. Over evolutionary time, the slit at the front of the mouth cavity has sealed shut in the armored larvae of ant lions that hunt in sand.
Only young sand-dwelling ant lions are mouthless. As adult insects, the 2,000 or so named species in the ant lion family, the Myrmeleontidae, have mouths and often a touch of the nature-calendar prettiness of damselflies, with long, lacy wings. But “they’re not the killing machines that the juveniles are,” says biologist Sandra Binning of the University of Neuchâtel in Switzerland.
Instead of mouths, the larvae rely on two long, toothed hooks at the front of the head. The youngsters dig pits in sand and bury themselves up to the hooks, ready to grab and stab ants or other insects that tumble in.
Each hook has a covered groove on the underside. When the hook