Epilachna varivestis

Mexican bean beetle ( Epilachna varivestis )

The Mexican bean beetle ( Epilachna varivestis ) is a beetle from the tribe Epilachnini the ladybug. This group includes mainly herbivorous species.

Features

The beetles have an oval outline and are about 6-7 mm long. The males are slightly smaller than females. They are straw colored or creamy yellow. In young animals eight black dots can be seen on each deck wings which are arranged in three rows. Older animals are darker until they take on a bronze color. During this time, disappear the points. The neugeschlüpften larvae are light yellow and are a maximum of 1.6 millimeters long. They have branched spines that are arranged in six rows. These are also first bright yellow, but darker and more noticeable so a few hours after molting at the tips. Full-grown larvae are 6 to 9.5 millimeters long and have a greenish- yellow color. The eggs are light yellow to orange- yellow, and 0.6 millimeters wide and 1.3 millimeters long.

Occurrence

The original area of ​​distribution is likely to be the plateau in southern Mexico. From there, the species has spread across Mexico and most states in the United States east of the Rocky Mountains. To the south, their distribution extends up to Guatemala, north to the New England states and into southern Canada. In 1933 it was reported that the type in Florida had been eradicated, but it was 1938 again found there and has firmly established itself again since 1942.

Way of life

The female lays 500 to 600 eggs, which are carefully mounted in groups from 40 to 75 on the undersides of leaves, so that they are perpendicular. In warm weather, the larvae hatch after a week in bad after 2 weeks.

The first hatched larvae stay together and eat at the sheet on which they are hatched. If the sheet is dry, they also eat the remaining eggs. If the larvae get older, they are divided into smaller groups. At pupation the larva depends on different plants, the pupation can take from 5 to 10 days. The adults are good fliers, which helps them in their search for food. The beetles begin in autumn, to look for leaves, where they can hibernate. They usually rest until spring, but the winter sleep may take longer.

The beetle as a pest

This beetle is one of the herbivorous species of ladybugs. He is regarded as a pest, since especially the larvae eat large amounts of plant material. Larva and Imago feed on crops and ornamental plants.

As a control, for example, helps Podisus maculiventris from the family of stink bugs, but also the fly Paradexodes epilachnae and the wasp Pediobius foveolatus be used for biological pest control.