Highway threatens 'killer' worm

It emerges by night from a dark damp corner of South Dunedin; a predator that kills its prey in the most sickening and horrific way.

It rears up on its haunches, shoots a stream of glue-like substance to disable its prey, injects spit to dissolve its innards, then sucks out the result to allay its vile appetite.

This is the peripatus worm, a creature that has been around for well over 500 million years and has been quietly protected and encouraged in a dank Caversham forest by Dunedin City Council staff and Forest and Bird for more than a decade.

But in the next few months, the worm described by University of Otago Emeritus Professor Sir Alan Mark as a "a sort of missing link between worms and the insect group", and "a living fossil", will be dragged into the light, amid concerns about its future.

Sir Alan said the worm had been a catalyst for significant replanting at Caversham.

The issue the worm is facing is the New Zealand Transport Agency's (NZTA) $49 million project to widen the Caversham highway to four lanes.

For the project, the NZTA has to buy land on the northern side of the motorway that has been given over to the peripatus, in an area Forest and Bird has been planting in an attempt to give the worm a better environment in which to thrive.

Council parks and reserves team leader Martin Thompson said the peripatus was discovered on a neighbouring property 15 years ago, when the reserve was just "a sycamore wilderness".

The NZTA had recently approached the council requesting a partial purchase of the front of two reserves by the road.

Those were the Lookout Point reserve, and another known as the Caversham Peripatus reserve.

"At this stage we're reviewing that proposal," Mr Thompson said.

The council had asked the NZTA in the past two weeks to come back with more information, including an entomological report.

Mr Thompson said the council had a long-standing arrangement with Forest and Bird, had worked with the organisation to revegetate the reserve, and most of the area that could be planted had been.

The work had been kept discreet so people would not disturb a "fairly sensitive" area. 

It would not be closed to the public, but he urged people to be careful if they visited.

New Zealand Transport Agency project manager Simon Underwood said the agency needed to take an area of the frontage of each of the reserves for its project.

The area would be about a house section deep along the existing highway.

The NZTA planned to apply for an alteration of a notice of designation it already had for the area under the Public Works Act.

While the entomological assessment report had not been commissioned, Mr Underwood said it would be.

"Whether there are peripatus worms in the section we are interested in is the first question.

"If there are, ... how do we manage that?"

Resource consent would be required, and it was likely that would be publicly notified, and would require a public hearing.

Peripatus or Velvet Worm 

• Fossils date back to the Cambrian Period; worms called "living fossils" because they have changed little in 570 million years.

• About 35 species in New Zealand, most undescribed.

• "Flagship species" in reserves, where saving them permits the survival of smaller native invertebrates, which die out if the vegetation is destroyed for farm use or roading.

• Has features in common with annelids (segmented worms such as earthworms) and arthropods (such as insects and spiders).

• Diet includes spiders.

• Can only live in moist places

• Males lay parcel of sperm on female's back, which dissolves through skin to fertilise.

• Females of one species give birth to live babies.

• Average length: 30mm.