The chorus cicada is one of the largest (80 mm wingspan) and loudest cicada of the 42 known endemic cicada species in Aotearoa.
As with all cicadas, the nymph that emerges from the egg looks like a wingless adult, but with large front legs for digging. They live underground for two to almost four years penetrating plant material to feed on sap, just like the adults above ground.
After their emergence from the ground they moult one last time before the adult males are soon ready start their chorus to attract females.
Male cicadas produce sounds using a pair of organs that are basically ribbed membranes and are called tymbals. Muscles inside the cicada’s body buckle the membrane inwards, and when the muscles relax, the membrane returns to their original state. This happens so fast that the tymbals rattle and create the song. The region of the abdomen where the tymbals are located is hollow, so it works as an acoustic resonator. Each cicada species has its own song and the females recognize the songs of males of the same species. Humans can also distinguish species by how they sound. You should try it!
Check these links for more info on the Chorus Cicada in NZ
iNaturalist.nz: Observations of Amphipsalta zelandica
Wikipedia: Information on Amphipsalta zelandica
Farm Forestry New Zealand: Forest and Timber Insects in New Zealand No. 44: Large cicadas
Click on the image to visit the official iNaturalist.nz observation.