Lauren Diepenbrock, assistant professor of entomology at the Citrus Research and Education Center in Lake Alfred, discovered the first appearance in 10 years of one such pest, the lebbeck mealybug, at a Highlands County orange grove on June 14, according to a pest alert from the Division of Plant Industry at the Florida Department of Agriculture and Consumer Services.

The lebbeck mealybug’s first Florida appearance occurred in December 2009 on a tallow wood plant in Palm Beach County, according to a Plant Industry pest alert at the time.

The pest didn’t spread any further, said Trevor Smith, the Plant Industry director, on Tuesday, and “it looked like it was fading into the background.”

Since the Highlands discovery, Plant Industry workers have found outbreaks of lebbeck mealybugs in two other Highlands citrus groves near Diepenbrock’s initial finding, he said. They continue to look for the bug.

Not much is known about what pesticides are effective against the lebbeck mealybug, Smith said. He speculated they may have moved into Florida groves because the pesticides used against the citrus psyllids are less lethal to the mealybug.

More than 90% of Florida citrus trees are infected with greening. Citrus growers in Jordan and South Africa have experienced major outbreaks of lebbeck mealybug that caused significant damage, including fruit losses of up to 50%, according to the Plant Industry alert.

The lebbeck mealybug cannot fly, Smith said. It is spread mainly by wind or attached to plant material and farm equipment.