State officials from the agriculture department confirmed the detection of little fire ants in Lanikai as well as at Kualoa Ranch in Windward Oahu.

The invasive little fire ants, which measure about one-sixteenth of an inch long, deliver a painful sting when disturbed and pose a major threat to crops and native species.

In Lanikai, the ants were found at six residential properties. At Kualoa Ranch, the ants were found in an isolated, 14-acre area on Kualoa Ranch that is currently not open to human foot traffic.

The Hawaii Department of Agriculture and Hawaii Ant Lab are currently treating the infestation in Lanikai, and working on a final master treatment plan for the ranch. At the ranch, officials plan to set up a buffer zone of 20 acres for treatment. Some locations within the zone are already being treated.

“Residents in uninfested areas around the state should always be on the lookout for little fire ants,” said Phyllis Shimabukuro-Geiser, chairperson of the Hawaii Board of Agriculture, in a news release. “Residents should also be careful before introducing any plants to their homes and yards regardless of where the plants are coming from. A simple peanut butter stick test can save your property from becoming infested with these invasive ants.”

In March, a Kaimuki mom who purchased a staghorn fern at the Punahou Carnival and brought it home later confirmed with the state agriculture department it had been infested with little fire ants. She and her infant reported being stung while in bed and noticed the ants crawling on the nightstand next to the bed, where the fern was placed.

Earlier this year, state officials said the ants were also found in Kaneohe and Ahuimanu neighborhoods, and the months-long treatment protocol for those areas is about halfway through. A survey of both areas last week did not detect the presence of any little fire ants. Monitoring continues for several years.

The ants were also detected in six acres of Mililani Mauka in June 2014, but following treatment, have not been detected there since February 2015.

Little fire ants, native to South America, were first detected on Hawaii island in 1999, and the population is widespread on that island. The ants are pale orange in color and move much slower than tropical fire ants. Their stings can cause large, red welts and may cause blindness in pets.

Residents of Oahu, Kauai and Maui County should survey their properties using peanut butter on a chopstick as a test. Any suspected invasive species should be reported to the state’s toll-free hotline at 643-PEST (7378).