English: Most commonly called grasshoppers, species in the family Acrididae vary greatly in shape, size and colouring, but all possess large hind legs well developed for jumping. They have short antennae, a short ovipositor and well-developed wings. Grasshoppers are active during the day and can produce sound by rubbing a row of pegs located on the hind legs against part of the forewings. Most species feed on grass (as their name suggest), but other vegetation is also consumed including leaves, stems and even dead eucalyptus leaves. The name locust is given to those species that are known to build up in large numbers. Locust swarms then migrate across vast areas causing almost complete destruction to all green vegetation, especially agricultural crops. The Australian plague locust is a native species of Australia and is one of the most economically important species in Australia. At times this species is known to build up in great numbers forming swarms that migrate across central and eastern Australia eating their way through almost anything green. This species can be recognised by the black patch on the tip of the hind wing and the red colouring on its hind leg. The body of female Australian plague locusts is usually green, but when swarming is brownish in colour.