Endangered species at home in aquarium tank

A rare and threatened aquatic moss has been found in an eel tank at Kelly Tarlton's Underwater World.

The fern-like underwater moss, fissidens berteroi, is known to exist in only three other places in New Zealand - under two bridges in the Wairarapa and in one spot in Auckland: the mouth of an outlet pipe draining an Onehunga spring.

Rare plant expert Peter de Lange made the find as he strolled with his two young sons past the tank, which houses three fat eels.

Mr de Lange, who works for the Department of Conservation, said he uttered "a few expletives" on spotting patches of the moss growing profusely on the tank's artificial rock walls last month.

Kelly Tarlton's marine curator Andrew Christie was taken aback to find out that the tank was harbouring a species so rare that the Department for the Environment says its extinction "would be a loss of international significance".

"We had no idea," he said.

Mr de Lange said aquarium staff "are apparently the first people to successfully - albeit unwittingly - cultivate a thriving population of the moss in New Zealand. A lot of people have been spending a lot of time trying to grow it - like the Auckland Regional Botanic Gardens - and have failed".

No-one understands why the moss has become one of the most endangered plants in the country.

The aquarium remains "baffled" about the moss' origins. A log was taken from a local stream 10 years ago and put in the tank, but there were no records of its origins, said Mr Christie.

Mr de Lange doubts the wood was the original source. Still, he said, the find suggested there was perhaps a second patch of the moss somewhere in Auckland.

Mr Christie said the find was "awesome" news for the aquarium.