Sentence:  Earless ghost swift <WSD>moths</WSD> become “invisible” to echolocating bats by forming mating clusters close (less than half a meter) above vegetation and effectively blending into the clutter of echoes that the bat receives from the leaves and stems around them. 
Meaning of the word marked with <WSD> tags:  A usually nocturnal insect of the order Lepidoptera, distinguished from butterflies by feather-like antennae.