Black Leafy Spurge Flea Beetle

Aphthona czwalinae is a species of leaf beetle known as the black leafy spurge flea beetle. It is used as an agent of biological pest control against the noxious weed leafy spurge (Euphorbia esula).

The adult beetle is shiny black and about 3 millimeters long. The female lays eggs on the soil next to leafy spurge, its host plant, during the summer months. The larva emerges in 16 or 17 days. It is white with a light brown head. It goes to work feeding on the roots of the plant throughout the winter and spring and then pupates in the soil until emerging as an adult in early summer. As the larvae weaken the roots the adults feed on the leaves and flowers of the plant, killing the plant outright or allowing infection by opportunistic fungi.