Cave Wetas Overhead!

Explanation: Watch your head! This low water passage tunnel provides ideal dark habitat for this most unusual of the already-unusual group of insects known as wetas. These are cave wetas, only distantly related to their other weta kin, all of which are found only in the amazing isolated natural laboratory known as New Zealand.

This species appears to be a Goldmine cave weta,
Gymnoplectron uncata.

There are some 18 genera and 60 species of cave wetas. They are remarkable for the length of their legs and antennae. Apparently the foot pads are very sensitive to vibrations ... a useful adaptation in the darkness of their environment for detecting approaching predators.

We found these wonderful specimens in old water tunnels ("water race trenches") carved for mining sites, on the Coromandel Peninsula of North Island, New Zealand.

We are in Kitahi Scenic Reserve in Puketui Valley, near the town of Puketui. As a local signpost informs, this was once a bustling gold mining settlement along the Tairua River, until it was mined out and the town folded by 1914.

Cave wetas are nocturnal.

These wetas were clustered on the low ceilings of these narrow tunnels, mostly toward the darkest portions of the stretches. Cave wetas overhead! Watch your hair ...

So don't be fooled by the brightness of my flash photography here. We wouldn't have even noticed their presence had we not been using headlamps.

Their appearance and numbers may be startling, especially when you suddenly discover them right against your face, but they are harmless.

Cave wetas feed on plants, some fungi, and sometimes other insects, and scavenge rotting fruit, helping to disperse nutrients in cave and forest ecosystems.

New species of cave wetas are being discovered.

We may have stumbled upon the Auckland cave weta, known locally by the Maori as tokoriko, and by its scientific name of Gymnoplectron acanthocera.

Cave wetas derived from a very ancient insect group, changing little over the eons as shown in their fossil records. Their diversity in New Zealand heralds a wonderful opportunity to continue to conserve this ancient lineage, as found in this forest preserve.

Acknowledgments:
My great thanks to Dr. Steven Pawson, entomologist with Scion, New Zealand, for hosting me on this hike and quest.

EPOW - Ecology Picture of the Week