Gum Leaf Katydid – Torbia viridissimaAdult Gum Leaf Katydids resemble a gum leaf, both in shape and colour. Their front wings look exactly a gum leaf, with the thick white vein in the middle. Their legs resemble fine twigs .This one was found on a load of yellow box branches at the Dookie seedbank and its camouflage is wonderful .
Katydids fed on eucalypt tree leaves. , they do not cause much, if any, economic damage.
Gum Leaf Katydids like to hide on the tips of the branch, but not on the top of the tree. This may help them to avoid the predation from birds.
Their antennae are longer than their body. It has been noticed that if its antennae is broken, it will re-grow to normal length after next moulting.
Their rear pair of legs are longer and stronger than the front and mid pair, but they look thinner than the hind legs of grasshopper. We seldom see them jump. Instead, they kick with their spiny hind legs if disturbed. All their legs are armed with spines.
Katydids and crickets are the major noise source in the field at night. The male produce sound, known as stridulation, to call for the female. They usually sing for the whole night. Both female and male have their hearing organs on their front pair of legs. Gum Leaf Katydid produce the sound by rubbing their two front pair of wings, or tegmen, together. There are the raised vein on the underside of both tegmen. By rubbing them together, just like rubbing the teeth of two combs against each other.