New Zealand - Arachnocampa LuminosaTweet
The glowworm has a four stage lifecycle:
- Eggs A female fly lays around 120 small eggs. After around 20 days, the young larvae hatch from the eggs.
- Larva Having hatched, the larvae build a nest, put lines down and feed. The lines are coated with sticky substances. It is this sticky coating which traps insects. The lines are then drawn up and the insects eaten. It is the larva that emit the light in order to attract the insects to the lines.
- Pupa The pupa is the stage between larva and the adult fly - it is equivalent to the cocoon stage in the butterfly lifecycle. The pupa is suspended from a thread from the ceiling and lasts around 13 days.
- Adult The adult glowworm resembles a mosquito. Apparently, the adults have no mouths as their only function is to reproduce and disperse the species. A male waits for the female to emerge from the pupa and mating takes place immeadiately. Adults only live for a few days. Hardly surprising, given they have nothing to eat with!
For the glowworm to survive, it requires humidity to prevent it from drying out, a sheltered surface to hang from and suspend its sticky lines, a calm atmosphere to prevent the lines from tangling, darkness to allow its light to attract food and a plentiful supply of insects to eat. Waitomo provides the perfect environment and a plentiful supply of insects brought into the cave via the river.