A second Queensland fruit fly has been found in Auckland.
The Ministry for Primary Industries (MPI) said on Thursday the single male fly was found in a trap on Wednesday in Northcote, on the North Shore.
It's the second fruit fly found on the North Shore in a week, the first trapped in Devonport on February 14.
A different kind, the Tongan fruit fly, was found in Otara on Tuesday.
A controlled area has now been set up in Northcote, preventing the movement of certain fruits and vegetables out of the suburb.
"We are totally focused on finding out if there is an incursion of the Queensland fruit fly in these areas," said MPI director General Ray Smith. "At the moment, these are two single males found quite some distance apart, and there's no evidence of a breeding population.
"We have an absolute commitment to tracking down these unwanted pests and ensuring New Zealand is free of harmful fruit fly."
The fruit fly is a serious threat to NZ's horticulture industry, and Minister for Biosecurity Damien O'Connor said protecting against an incursion is a costly business.
"A guesstimate would be about $1 million per fruit fly."
It's not the first time a Queensland fruit fly has been discovered in the upper North Island, but only once before has a population been found. That was four years ago, and it took $16 million and 10 months to eradicate.