A whiter shade of snail
A rare white-bodied giant snail has been found by members of the Waimea Tramping Club in Kahurangi National Park.
The rare albino giant Powelliphanta hochstetteri hochstetteri snail, a "fascinating find", was spotted in the Flora Stream area during a tramping club party's recent trip, a Department of Conservation spokesperson said today.
The snail had its characteristic golden brown-spiralled shell but with a body that was a glowing white rather than the usual deep black colour.
Motueka resident Bill Brough, who has seen quite a number of Powelliphanta snails in his tramps, was one of three people to see the remarkable snail, he said.
"Our group had seen three or four snails already that morning as it had rained and they’d come out in the wet conditions. Then I saw the white snail and went 'wow'. We were excited to see it, knowing how extraordinary it was."
Mr Brough said no patterning was apparent on the albino snail he saw which he described as being "off-white like Milky Bar white chocolate in colour".
Department of Conservation Powelliphanta expert Kath Walker said it was only the second instance of an albino Powelliphanta snail she had come across, in more than 30 years studying the native snails.
The first was 23 years ago in 1988, which was a Powelliphanta gilliesi gilliesi snail from Mt Burnett in Golden Bay which was only partially albino. It had dark internal patterning still visible on its otherwise white body and, like the recent find, still had a normally-coloured shell, she said.
Ms Walker said albinism was known to occur in many animal species around the world.
The absence in pigment, which could be partial or complete, was due to a genetically-inherited defect in the enzyme which produced melanin.
She has since searched the spot where the latest white Powelliphanta was seen but was unable to find it.
‘I was curious and interested to see the albino snail as it is exceptional to come across one. From the photos it looks to be an adult snail at least 10 years old and I am amazed it has survived this long. Its white body would make it clearly stand out to be picked off by weka or other predators.’
Powelliphanta snails, found only in New Zealand, are the giants of the snail world with striking spiralled shells in an array of colours and patterns. They are carnivores, their favourite prey being earthworms but they also eat slugs.
The white snail grows up to 80mm across.
The species is endangered due to predation by introduced pests.