Two new species of wētā have been found on Stewart Island and in the northern Fiordland region.
Two new species of wētā have been discovered and named, in a feat described by conservationists as being “remarkable”.
Wētā have been around long enough to see dinosaurs come and go, and have evolved into more than 100 different species.
The species are categorised into five groups: tree, ground, cave, giant, and tusked wētā – both of the new species live primarily on the ground.
The first new species, the Anderus Rakiura, was named after the Māori word for Stewart Island, where this species is endemic. These wētā are small and slim, and are dark brown with a prominent, large cream patch.
The second discovery, the Anderus Pipiwai, meaning “a wet place”, was discovered in Fiordland.
Anderus Pipiwai wētā are small and dark in colour, often appearing nearly black in some areas.
Its legs are dark brown, but can appear yellow brown on certain surfaces.
Steven Trewick, a professor in evolutionary ecology at Massey University, was involved with finding both new species, and said he was “pleased with the discovery”.
“Although there were 20 or so species, it was quite clear that these were two very different lineages,” Trewick said.
“They look different and genetically they’re quite different and unrelated to other species.
“They’re not the biggest; they hide during the day in holes in the ground, which they close over with little soil lids.
“When they hide away during the day, people don’t see them.
“They have much more abundance in native forest habitats and have been excluded from modified habitats, such as agricultural land and urban areas.”
Trewick stated that the process of discovering a species was “quite drawn out” and required collaboration with local iwi and hapū, as well as the Department of Conservation.
“We’re a weird bunch that quite like going out in the forest at night because that’s when you see lots of extraordinary biology happening – because so much of New Zealand’s biology is nocturnal,” he said.
“Over the years, specimens are connected and noted and commented upon, quite often for conservation purposes or biodiversity purposes.”
Trewick said surveys are done to identify how many different kinds of a species were found in one area.
“Quite often, that reveals that there are species that haven’t been formally recognised, so can be counted,” he said.
“There’s actually quite a lot of wētā species in New Zealand, but a large number is still undescribed.”
“Quite often people are aware, as there’s ‘a kind of wētā that you find down there’ – but it hasn’t got a name,” Trewick said.
“That’s very problematic because it means no one is quite sure how to refer to it.”
This meant the naming process was an important step in identifying a new species, Trewick said.
“We could just say are there wētā, but wētā means any of the one-hundred-plus species,” he said.
“That doesn’t fairly describe the ecological diversity.
“Having names is important, and in law, and to have something that we can refer to that can be recognised for conservation.”
He said the “incredible diversity in New Zealand” meant that not all wētā species were related to one another, and the two new additions have relatives in other parts of the world.
Dean Baigent-Mercer, regional conservation manager for Forest and Bird, said it’s a “real buzz” when a new species is discovered.
“It’s a remarkable feat to go through that period of discovery,” Baigent-Mercer said.
“We have a lot of unnamed species in the country, whether they be plants, insects or fungi.
“Once it goes through the scientific work to describe a new species, then you can work out prioritisation in terms of pest control and how threatened it may [or may] not be – so it’s a very important process.”
Baigent-Mercer said the difference between the two species highlighted the uniqueness of the regions in which they are found.
“The discoveries are a spotlight on the uniqueness of those particular places,” he said.
“They will be in a relationship with everything else that is around them, and it opens up the universe of the whole habitat that they live in.”
Eric Edwards, the Department of Conservation’s science advisor, said the recent discovery was great news for conservation.
“Wētā includes many of New Zealand’s iconic invertebrates with more than 100 species currently known across the country,” Edwards said.
“Every time a new species is uncovered, it deepens our understanding of regional endemism and shows how not only is New Zealand’s wildlife internationally distinct, but regionally too.
“The more we learn about nature, the more we realise there is to learn.”
Jazlyn Whales is a multimedia journalist based in the Christchurch newsroom.