The lifecycle of a Glowworm is in four stages and takes about 11 months. Eggs are laid in clutches of 30-40 on walls and ceilings. Immediately on hatching from the egg, the larvae emit a light, build a nest, put down lines and feed. Sticky substances on the lines trap insects and these are drawn up and devoured.
The larvae stage is the longest phase in the creature's life and lasts around nine months. It then turns into a pupa in a cocoon and emerges as a two winged flying insect, which looks like a large mosquito.
The adult fly lives no longer than a few days as it has no digestive system and so cannot eat. Instead it uses this time to mate and lay eggs. The glowworms found in the Waitomo Glowworm Caves is a species unique to New Zealand.
The female fly lays around 120 small spherical eggs. Within around 20 days the young larvae hatch from the eggs and crawl away.
Glowworm's feeding lines
After hatching the young larvae build a nest, put down lines and feed.
Sticky substances on the feeding lines trap insects and these are drawn up and devoured.
Even at this small size, less than 3 millimetres long, they emit a strong visible light and slowly grow over 9 months to the shape and size of a matchstick.
The pupa is the same as the cocoon stage in the butterfly lifecycle; it is the stage between the larva and the adult fly. This will last about 13 days with the pupa suspended by a thread from the ceiling.
The adult glowworm looks like a large mosquito. They have no mouth and their only function is to reproduce and disperse the species. Usually a male is waiting for the female to emerge from the pupa, mating takes place immediately and the cycle continues. Adult glowworms live no longer than a few days