Grasshoppers, crickets and katydids all belong to the Order Orthoptera. Most are plant-feeders and some, such as locusts, are agricultural pests. Most species produce sounds by rubbing various parts of their bodies together, particularly the bases of their wings. This a moderately large group of insects with almost 3000 species estimated to occur in Australia.
The beautiful Queensland Spotted Pyrgomorph, Greyacris profundesulcata (Family Pyrgomorphidae).
Caedicia is probably the largest genus of Orthoptera in Australia, containing many very similar looking katydids (Family Tettigoniidae).
Both male and female Wood Crickets, Epacra spp. (Family Gryllacrididae), may sing in times of stress.
A Dead Leaf Grasshopper, Goniaea sp. (Family Acrididae) with a prominent arched crest on the thorax is well camouflaged while resting among dead leaves in dry eucalypt forests across Australia.
Almost all grasshoppers, crickets and katydids have enlarged hindlegs that are designed for jumping. Most have thickened forewings that form leathery wing covers to protect the delicate hindwings that fold up underneath. However in some species the wings are very short or completely absent.
Grasshoppers and locusts generally have short antennae, hearing organs on the abdomen, make sound by rubbing the hind legs against the forewings and are herbivorous.
Crickets and katydids generally have long antennae, hearing organs on the forelegs, make sound by rubbing the forewings together and may be predatory, omnivorous, or herbivorous.
The Hedge Grasshopper, Valanga irregularis (Acrididae), has short antennae.
The Spiny-legged Katydid, Paracaedicia serrata (Tettigoniidae) has long, enlarged hindlegs and long, fine antennae.
Most species of grasshoppers, crickets and katydids are plant-feeders, but a few are predators.
Almost all grasshoppers, crickets and katydids have enlarged hindlegs so that the animal can jump to begin flight or to escape its enemies.
Many are capable of producing sound, usually by rubbing the bases of their forewings together. Not surprisingly, grasshoppers and their relatives also have 'ears', most often on their front legs or at the base of their abdomens.
Immature grasshoppers, crickets and katydids are nymphs that look like small adults without wings. The wings develop more at each moult (gradual metamorphosis).
Nicsara spuria (Tettigoniidae) nymph moulting to adult with fully developed wings.