Skitters, are an aggressive space faring species of six-legged reptilian clawed insectoid aliens with two prehensile arms. They are nocturnal, speak in a kind of strange language with a manbidle equipped mouth and possess light-green eyes with vertical black pupils. They appear to have armor that covers their body except for their head and legs. They invaded the Earth in the early 21st century and destroyed all major cities. At first they were not engaged because humanity thought they might be peaceful. They "harness" children using a centipede-like parasite to control the children's minds so they can communicate with humans. They use bipedal Mechs and airships.
Source: Falling Skies series