Glow worms are well-known throughout the world as remarkable insects that give off bioluminescent light. But New Zealand is home to an amazing version of glow worms – the Arachnocampa luminosa – and they are responsible for one of the most stunning natural spectacles in the world.
The common glow worm, or Lampyris noctiluca, is actually a beetle, not a worm, but the Arachnocampa luminosa is a species only found in New Zealand, and is in fact a type of gnat.
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These fungus gnats are responsible for the amazing blue twinkling lights seen covering miles of cave networks in the country. Tourist attractions such as the Waitomo caves enable you to enter huge caverns that are filled with Arachnocampa luminosa.
The carnivorous gnats tend to live in dark, damp spots and it is the larvae that produce the bioluminescent light they give off, which is created through a chemical reaction between an enzyme and oxygen.
The larvae produce silk which they make into a nest on cave ceilings and then hang threads covered in sticky mucus. Prey is attracted to the larvae's glow and then caught on the threads.
The Waitomo Glowworm Cave is one of several glow worm tourist attractions in New Zealand and visitors can tour by boat around the vast network of caves, lit up by the animals. It was first properly explored in 1887 by Māori chief Tane Tinorau and the English surveyor Fred Mace. The limestone caves were formed over millions of years and there are around 300 known caves in the Waitomo region. But Arachnocampa luminosa can be found in many areas across New Zealand, including Te Anau and Wellington Botanical Gardens.
Top image: New Zealand glow worms. Credit: Martin Vlnas/Getty Images
