Catocala fraxini
Blue Underwing (Catocala fraxini )
The Blue Underwing (Catocala fraxini ) is a butterfly (moth ) from the family of cutworms ( Noctuidae ). It is one of the largest species of the genus of the Ribbons ( Catocala ).
Features
The moths reach a wingspan from 90 to 98 mm (100 to 110 mm). The forewings are pale gray to whitish gray or brown. The inner and outer transverse line are white, black margins and strongly serrated. A kidney blemish and a rhombic, bright spot in the dorsal position to the kidneys blemish are constantly present. The wavy line is usually only hinted at something darker than the ground color. In the outer region of the Saumfeldes sit black, interneural Arrow stains. The fringes are also white.
The hind wings are dark brown with a broad blue band running ungezackt in a semicircle from the front to the back edge. The fringe and the outer region of Saumfeldes are white with black spots interneuralen arrow.
The bottoms show a strong contrasting black transverse line approximately in the region of the outer transverse line and a gray hem, separated by a white band. The hind wings show additionally a black, crescent-shaped Diskalfleck. The hem line is black, the fringe whitish.
Color and drawing are somewhat variable. the
- From. Moerens shows darkened forewing; except the outer transverse line and the diamond-shaped, bright spot in the dorsal position are to renal blemish
- From. gaudens is a very light form, in which the black drawing elements are almost extinct.
The egg is hemispherical, flattened at the base. It is brown in color with a yellow band below the Mikropylzone. The surface shows strong longitudinal ribs, about every second rib reaches the Mikropylzone.
The caterpillar is gray in color and covered with fine black spots. They are 65 to 75 mm long. The back line is only weakly developed. A flat, transverse elevation on the eighth segment is edged with black behind. The head is relatively large, light brown in color with a dark brown wetting.
The dark red-brown doll is relatively lean and strong blue frosting. The cremaster is relatively short and wide, and is staffed with two long, curved bristles and many shorter bristles.
Geographical distribution and habitat
The distribution area extends over almost the entire central and northern Europe and parts of southern Europe. The species is largely missing in Portugal, the Mediterranean islands (except Corsica), in Greece, in the north of Scotland, in northern Scandinavia and in Northern and in Southern Russia. The distribution area extends beyond Europe to the north of Turkey, to Siberia and to the Far East ( Russian Far East, Korea, Japan). In Austria, the species is found in all states; Moderately often to rarely occurring.
You can find this type on the edges of mixed deciduous forests, river banks and avenues. More rarely, the butterflies can also be found in old, overgrown gardens and parks. In the mountains you can find this kind only to the deciduous forest border.
Way of life
The blue ribbon is univoltine, that is, there is formed only one generation per year. The nocturnal moths fly from mid-July to mid-October. The moths drink means of their proboscis occasional tree or juices of fruits and - like all ribbon types - easily baited. The moths rest on tree trunks during the day and are well camouflaged by the restless drawing of the upper wing surface. At night, artificial light sources are occasionally fly and the moth then settle down in the area. From the overwintering eggs hatch the caterpillars in May. The caterpillars eat the leaves of aspen particularly (Populus tremula ), rarely the leaves of ash trees (Fraxinus ), oak (Quercus ), birch (Betula ), beech (Fagus ), maple (Acer), elm (Ulmus ), Linden ( Tilia ) and alder ( Alnus ) and True weeping willow (Salix babylonica ). They move like a spanner and rest during the day snuggled up close to the bark of their food trees. They pupate in June in a slight cocoon among leaves. The species overwinters in the egg stage.
Endangering
The blue ribbon is in the Red Lists of the Federal Republic of Germany a kind of early warning, ie the type could in future be jeopardized by the continued destruction of their habitats. However, the situation in Germany is very different. In North Rhine -Westphalia, the species is threatened with extinction (category 1), in Hamburg, Lower Saxony and Rhineland -Palatinate she is at high risk (category 2) and in Mecklenburg- Vorpommern, Saarland and Saxony -Anhalt, the species is considered endangered ( category 3).
In some provinces (Lower Austria, Burgenland) as endangered, but reported as not at risk - in Austria, where the blue ribbon is the largest native owl, it is moderately frequent to rare and protected throughout - gesamtösterreichisch.