Beet armyworm
Preparation of Spodoptera exigua
Spodoptera exigua, also known as beet or knotweed Seidenglanzeule, is a butterfly (moth ) from the family of cutworms ( Noctuidae ).
- 5.1 Notes and references
- 5.2 Literature
Features
Butterfly
The wingspan of the butterfly is 26 to 33 millimeters. Specific type are the very narrow front wings that vary in color from yellow brown to gray-brown. Kidney and in particular a ring stain are usually filled reddish. The transverse lines are duplicated, but usually in the form indistinct. The wavy line is indistinct. At the hem there are some black dots. Very striking are the shiny white-colored and iridescent hindwings and the striking brown veins.
Egg
The egg is rounded, flattened at both poles and provided with strong longitudinal ribs.
Caterpillar
Adults caterpillars show either a greenish or gray-brown ground color and a lighter ventral side. The topline is dark brown and interrupted while the wide side stripes shimmering pale ocher yellow.
Doll
The yellow-brown doll is characterized by several small peaks at the blunt cremaster.
Geographical distribution and habitat
Spodoptera exigua occurs worldwide, but preferably in tropical and subtropical regions. In Europe, she is down to earth in warmer zones of the Mediterranean basin and flies the northern areas as a migrant butterfly. The animals are mainly to be found in the growing areas of different crops.
Way of life
The nocturnal moths like to fly to artificial light sources as well as scale bait. The eggs are in small opportunity, covered with hair wool from the anal tuft of the females stored. Often, the caterpillars are introduced to central Europe with vegetables or fruit. They eat extremely polyphagous on many crops, such as paprika, cabbage, bean, potato, onion, tomato, alfalfa, corn, cotton, lemon, sugar beet, asparagus, vine and can also be harmful in plantations. Sometimes they were also smartweed ( Polygonum ) or wind types ( Convolvulus ) found. As a defense against enemies, such as ants ( Formicidae ), they are sprayed by the crawler with an oral secretions from the mouth parts, which contains surfactant. There are attempts to apply with the help of pheromones a check against a mass propagation. In the subtropics, moths and caterpillars over the entire year living in an unbroken succession of generations. Butterfly found in Central Europe perceived as immigrants, if they occur in the spring. Late moths may have evolved as descendants of immigrants in the early summer animals. Severe winters can not survive the caterpillars and perish.
Endangering
Spodoptera exigua is flying to Germany the year, in different frequency and is classified on the Red List of Threatened Species as Irrgast or hiking moths.