Gnaw-jaws are gigantic insects found on Jakku that are roughly a third of a meter long. They have many legs, chitinous plates, and big scissor-like mandibles.
They live in warrens of tunnels beneath the sand, coming out at night. They generally avoid people but they'll take advantage of someone who's weak or asleep. If forced to camp in the desert a circle of powdered barium will keep them away.