Ragweed Leaf Beetle

Appearance

''Ophraella communa'' can reach a length of 3.4–4.1 millimetres in males, of 3.9–4.3 millimetres in females. The head is yellowish, with dark brown spots at the back. Body is coarsely punctured. Antennae are dark brown. Pronotum is yellowish or pale brown, with three black or dark brown spots. Elytra are yellowish or pale brown and show dark brown longitudinal stripes.

Distribution

This species is endemic to the Middle and North America and it has been introduced in Southern Asia and in Europe, where it landed in 2013.

Behavior

This species feeds almost exclusively on leaves and flowers of the family ''Asteraceae'' tribe ''Heliantheae'', e.g. sunflowers and rough cockleburs , with a marked predilection for common ragweed , which is invasive in Europe and Asia.

The eggs are laid on the underside of young leaves of the host plants. The eggs are pear-shaped, with an hexagonal microsculpture. They are at first yellow, but quickly change their color to orange. Before the pupation, the beetles form cocoons on a leaf tip. Pupation lasts one to two weeks. After hatching, the adults remain on their host plants, but later they can migrate up to 25 km within one day.