Beetles create a “bug apocalypse” in Brazil’s Northeast

At the beginning of October, a cloud of countless reddish beetles descended on the small town of Pio IX, in the south of the northeastern Brazilian state of Piauí. Hundreds of local cashew-farming families looked on in horror as the insects arrived like a biblical plague. 

They quickly landed on the trees and ate everything they saw: fruits, leaves, and shoots. Other fruit trees, such as umbuzeiros and seriguelas, were not spared either.

Piauí is Brazil’s second-largest producer of cashew fruit, best known outside the country for its nuts. About 30 percent of the local cashew production was lost in less than a month.

At a loss for what to do, the farmers realized that the animals were attracted to light and had nocturnal habits, with the peak of their destruction generally occurring between 6 pm and 1 am So they improvised light traps, directing beams of light at a single point and trapping the pests in 60-liter drums. Images of these huge containers filled to the brim with insects went viral on social media.

The animal’s species, Liogenys pilosipennis, was only cataloged in 2015, and there had been no records of it attacking crops. Experts from public universities began studies to learn more about the insect’s habits, but the results will take some time.

Local government and state agricultural agencies were caught off guard. The agriculture secretariat of Pio IX said that since it was a relatively...