Maoricicada nigra

M. nigra frigida are found in alpine, semi-tundra areas with permanently moist soil and Asteraceae-dominated terrain.^[5] M. nigra nigra live in an alpine environment and have been observed in subnival (winter snow only) and nival environments (permanent snow and ice).^[5]

The lifecycle of M. nigra is, like many of New Zealand’s insect species, understudied.^[5] Female cicadas will cut notches into tree branches and lay eggs in them using a specialised appendage called an ovipositor.^[9] Nymphs hatch from the eggs and drop to the ground to find soil.^[9] Cicada nymphs are creamy-white and have claw legs to dig into the soil, about 40cm below the surface.^[9]

Cicadas spend the rest of their nymph stage, the longest stage of their life (from 3 to 5 years), below the soil and will shed their skin multiple times as they grow bigger.^[9] Moulting is the process of shedding an exoskeleton which allows the cicada to grow.^[10]

When they are larger and more developed, the nymphs burrow to the surface and find a high place to climb up during the night in places such as trees and shrubs.^[9] The cicadas will shed once more as an imago signalling their maturation into adulthood.^[9]

The adult cicadas will fly away in the morning to find a mate and reproduce. Male M. nigra sing to attract a mate using specialised structures called tymbals to produce noise.^[8] Tymbals are located on the side of the male’s abdomen and are pushed out and popped back in repeatedly to make a sound.^[8] Both subspecies of M. nigra alternate between two contrasting notes by synchronising the low-frequency doublets (clicks) from either (left or right) tymbal and alternating the high-frequency doublets.^[8] The song of a male M. nigra makes an “er-chit- er-chit- er-chit- er-chit… ” sound.^[8]

Both female and male M. nigra have tympana; ear-like structures used to hear noise.^[11] Tympana are connected to an auditory system which allows for the intake of sound.^[11] Their auditory system works so well that when a male sings he must ensure he doesn’t deafen himself by creating a fold in his tympanum. M. nigra are most found as adults during January and February but have an estimated season from November to April.^[7]

Both nymph and adult forms of M. nigra are xylem-feeders.^[5] They use their piercing-sucking mouth parts, characteristic of the Hemiptera order, to feed from sap in plant roots (nymphs) and tree branches (adults).^[9]

General predators of cicada are parasitic wasps which infest the cicada eggs, beetles which hunt nymphs, and fungal parasites that can kill nymphs and adults.^[5] Other predators include spiders, birds, and mammals, which can eat cicadas as nymphs and adults.^[5] Predatory mammals, introduced to New Zealand as early as the 1800’s,^[12] pose a threat to cicadas even in alpine environments.^[13]