The new bugs Whanganui resident Lynne Douglas has found in her garden will eventually keep a pest plant to low levels, Horizons Regonal Council's Craig Davey says.
The tiny bugs and their slug-like larvae were new to Mrs Douglas, a keen photographer and observer of nature. They were eating the bushes (Buddleia davidii) she had planted in her garden to attract butterflies.
Her bushes may not last long, because they are a species unwanted in New Zealand and a biological control insect species has been released to control them.
Buddleia was introduced from China in 1946, and became a pest plant, especially affecting new forestry plantations.
It can tolerate a wide range of conditions and spreads fast through seeds and suckering, Mr Davey said. The bushes form a canopy 3-4m high, with smaller seedlings underneath, and they smother other plants.