In search of The Lost Canyon maggots

WATCH: We brave bats, eels and terrifying climbs in the dark, in search of rare New Zealand glow-in-the-dark maggots.

WE'RE wading through a gushing stream at the mouth of an underground canyon in search of rare New Zealand maggots. An eel brushes my ankles, then a tiny bat dives bombs our heads.

Welcome to the well-hidden home of Arachnocampa luminsa - an incredible fly larva or  "glow worm" that behaves remarkably like a spider.

This clever maggot, about one cm long, only found in New Zealand, secretes a fishing line-like thread that it dangles from dark cave ceilings.

Then, in the darkness it attracts its prey (small flying bugs) by lighting up part of its dung-filled rear like a glow-in-the-dark bait. The maggots extraordinary efforts to entrap their prey has had scientists fascinated since 1871 when modern science recorded what the Maori's already knew.

We're venturing towards a huge colony of Arachnocampa luminsa in the aptly named Lost World Canyon.

It's in Waitomo in New Zealand's North Island. Just getting to the cave entrance is a test of nerve. We are guided here by the team from Waitomo Adventures.

Step one of the tour is a doozy. It's a vertical drop 100m down into what looks like a Hollywood special effect.

The Waitomo team encourage you to lower yourself  - yes, lower yourself - through a huge crack in a massive rock wall formed a millennia ago, down to find the special maggots. The rock walls are emerald green with ferns,vines and all manner of ancient life stretching upwards to the sun.

We're going down. Into the darkness I grip my lifeline, a sturdy climbing rope and safety clips. The thick vines on the walls, are "grown as ropes for the Aussies" our Kiwi guides joke. We laugh nervously. Dressed in white abattoir gumboots and wet suits we lower ourselves bit by bit down into the canyon floor.

The water course we follow is knee deep and is about 12 degrees, beautiful to drink, bloody cold to wade in.  We enter the"blackwater"  dark underground rivers and waterfalls.

Our guides are magnificent, carefully securing our walking ropes and encouraging us to climb up  and down waterfalls and jump into blackened rock pools.

Rock walls reach out like giant potato chips and giant rock slabs below our feet are shaped like brains. Dripping wet stalactites and stalagmites decorate our trail. We're now passing through a cavern favoured by The Hobbit special effects production team. Beauty on a huge scale.

Finally we make it. We're in the "glow worm" cave. Lights off. These incredibly sensitive little creatures don't like being disturbed.

Sitting quietly peering in wonder up at the truly spectacular glowing lights above me, this is a moving, almost spiritual experience.

That something so small could be so beautiful is humbling. They glow with a greenish fluorescent brightness that our videos and photos can never do justice.

Their lights spread across the entire ceiling, all symmetrically spaced living in the darkness and ever present gushing waters.

If you're not fit I'm not quite sure how you'd get back out of here, the vertical climb 100m up a slippery steel ladder was a test in itself.

A few kilometres up the road there is a tourist man-made cave with purpose bred "glow worms" but its hard to be beat the real experience of The Lost World Canyon maggots.

The author travelled courtesy of travel.com.au