Acauloplacella (Acauloplacella) queenslandica Rentz, Su and Ueshima
This katydid was discovered last night in the garden. It probably overwintered as a nymph and is now an adult just as the temperatures are rising. It is one of four species recently described in the genus. (Rentz, et al., 2010). All species are known from the northern rainforests along the east coast of the continent. Many others in this and other genera occur in New Guinea, Borneo and southeast Asia. They are nocturnal and are plant feeders. They have a low, stuttering call that is heard after dark. During the day the katydids usually perch on the underside of a leaf with the wings somewhat flattened rendering a boat-like appearance to the insect.
One of the distinctive feature of this group is the projecting anterior margin of the forewing which not only covers a portion of the pronotum (thorax) but also conceals the thoracic "ear of the katydid.
You can see this very well on the photo above.
This species has been called the Chirping Leaf Mimic and is very delicate. It uses its green colour and secretive behaviour to avoid being eaten. It has fairly long and sharp tarsal claws that enables it to cling to its substrate and not only to avoid being picked-off by a predator (or collector) but to hang upside down.
Rentz, DCF, Su, YN, Ueshima, N. 2010. Studies in Australian Tettigoniidae: Australian pseudophylline katydids (Tettigoniidae: Pseudophyllinae; Phyllomimini). Zootaxa, 2566: 1-20.