Small sand thyme tensioner
| Small sand thyme tensioner | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Small sand thyme tree ( Scopula decorata ) (due to unfavorable lighting conditions, the base color has unnaturally turned a blue shade) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Scopula decorata | ||||||||||||
| ( Denis & Schiffermüller , 1775) |
The sand thyme small spanner ( Scopula decorata ), also called thyme steppe lawn spanner , thyme steppe lawn spanner or thyme lawn spanner , is a butterfly ( moth ) from the spanner family (Geometridae).
features
The moths reach a wingspan of 22 to 27 millimeters, the following generations often only 17 millimeters. The basic color is creamy white to yellowish white. The transverse lines are colored brown, the drawing elements of the border area are mostly gray. The inner transverse line and the central band are only weakly developed, often only indicated by elongated spots or rows of spots. There where these elements touch the front edge, clear costal spots are formed. In contrast, the outer transverse line is very clearly drawn. In the front and the rear half, a spot is roughly centered on the outer transverse line. These spots are only present on the forewings and are markedly lighter than the outer transverse line itself. The outer transverse line is serrated; triangular spots emanate from it and point to the outer edge. The hemline usually consists of brown, very elongated spots. Triangular spots also start from the hemline, but their tips point towards the root; the triangular rows of the outer transverse line and the hem line are therefore opposite. If the drawing is strong, the rows of triangles leave just a light, jagged line in the basic color between them. However, the rows of triangles emanating from the hemline are often very blurred. The fringes of some specimens are also covered with very small, brown or gray triangular spots.
The egg is light green. The outside has numerous longitudinal ribs that intersect with weaker transverse ribs.
The caterpillar is relatively long and slender. It is yellowish in color, reddish on the back with a black, double back line. The side lines are laid out in white.
The doll is 7.5 to 8.2 millimeters long and relatively slim. It is greenish-brown, at the rear end red-brown. The wing sheaths are greenish and moderately shiny. The cremaster is tongue-shaped and somewhat flattened dorsoventrally. He has six hook bristles.
Geographical distribution and habitat
The sand thyme sprout occurs in a large area from Morocco and the Iberian Peninsula in the west, across North Africa, southern and central Europe, Asia Minor , the Caucasus region, southern Russia, northern Iran , various Central Asian mountains, Tajikistan , Afghanistan to western China. In the north the distribution area extends to the Baltic States and southern Finland. According to its large distribution area and the partly quite isolated distribution islands, the species has already split into several subspecies, which are, however, connected to one another by transitional forms.
The species is always quite rare in its entire range and restricted to smaller, often isolated areas. It occurs only in dry, warm areas where the main food plant of the caterpillars, namely thyme, grows. This only grows on extremely nutrient-poor soils and in places that are otherwise almost free of vegetation. These conditions are e.g. B. met in sand and gravel pits, on heathland with sparse pine vegetation, on sand dunes on the coast, on dry grass, in fallow land and rock steppes. North of the Alps, the species is therefore limited to an altitude of up to 300 meters. In the Southern Alps and the Balkan Peninsula the species rises up to 1600 meters, in Turkey, Northern Iran and in some Central Asian mountains up to 3100 meters.
Phenology and way of life
The species is usually bivoltine in Central Europe , ie two generations are formed. Under favorable conditions south of the Alps and in warmer regions, e.g. B. North Africa is made up of three generations. In contrast, only one generation is formed under unfavorable conditions in Northern Europe. The subspecies congruata z. B. in Morocco is univoltin above 1200 meters, bivoltin around 100 meters and trivoltin in the plain. The moths fly in the north of the distribution area in only one formed generation from the beginning of May to the beginning of September, at higher altitudes only from the end of June to the beginning of August. In two generations, the moths appear in early May to early July and then again from mid-July to early September. In areas where three generations are formed, the moths appear as early as the end of March. The moths can only rarely be observed flying during the day; they rest in the vegetation, but can easily be roused. They are usually crepuscular and nocturnal and come to artificial light sources. The moths suck nectar from thyme flowers.
The caterpillars presumably feed monophag on sand thyme ( Thymus serpyllum ). The caterpillars may also eat other thyme species; this has not yet been proven with certainty. From France there is also evidence of lemon balm ( Melissa officinalis ) and common vertebrate ( Clinopodium vulgare ). Breeding has also been successful with oregano ( Origanum vulgare ). The caterpillar overwinters.
Systematics
The species was first scientifically described in 1775 by Michael Denis and Johann Ignaz Schiffermüller under the name Geometra decorata .
Currently the species is divided into six subspecies: the nominate subspecies Scopula decorata decorata Denis & Schiffermüller, 1775 (Southeast Europe, South Russia, North Italy, South France), Scopula decorata violata Thunberg, 1784 (North Germany, Baltic States), Scopula decorata congruata Zeller, 1847 (Iberian Peninsula , South Italy, North Africa), Scopula decorata armeniaca Thierry-Mieg, 1916 ( Armenia ), Scopula decorata przewalskii Viidalepp, 1975 ( Mongolia ) and Scopula decorata eurhythma Prout, 1935 (West China).
The western subspecies is listed by some authors as a separate species Scopula congruata Zeller, 1847.
Danger
The small sand thyme tree is acutely threatened with extinction in Germany. Currently there are only smaller deposits in three federal states, in Baden-Württemberg, Brandenburg and Saxony. In Brandenburg and Saxony it is classified in Category 1 (threatened with extinction), in Baden-Württemberg in Category 2 (critically endangered). However, the species may have been rare even earlier. Nevertheless z. B. in Brandenburg the population demonstrably declined sharply. The species has been extinct in the Netherlands since 1942.
swell
Individual evidence
- ↑ a b see red lists at science4you with alternative names
- ↑ Jan Pactočka: The pupae of the tensioners (Lepidoptera, Geometridae) Central Europe: subfamily Sterrhinae. Bonn zoological contributions, 51 (4): 269–296, Bonn 2002 ISSN 0006-7172 PDF ( Memento of the original from May 17, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (2.9 MB)
- ^ Ole Karsholt: The lepidoptera of Europe: a distributional checklist. 380 pp., Apollo Books, Stenstrup, 1996 ISBN 87-88757-01-3
- ↑ Thomas Sobczyk and Jörg Gelbrecht: On the area regression of the species Scopula decorata ((Denis & Schiffermueller), 1775) and Pseudophilotes vicrama (Moore, 1864) in Germany (Lepidoptera, Geometridae et Lycaenidae) bound to thyme (thymus). Märkische Entomologische Nachrichten, 6 (1): 1–16, Potsdam 2004 ISSN 1438-9665
- ↑ Hausmann, pp. 280-3
literature
- Arno Bergmann: The large butterflies of Central Germany. Volume 5/1: Spanner. Distribution, forms and communities. Urania-Verlag, Jena 1955, DNB 450378403 .
- Günter Ebert (Hrsg.): The butterflies of Baden-Württemberg Volume 8, Nachtfalter VI (Spanner (Geometridae) 1st part), Ulmer Verlag Stuttgart 2001. ISBN 3-800-13497-7
- Walter Forster , Theodor A. Wohlfahrt : The butterflies of Central Europe. Volume 5: Spanner. (Geometridae). Franckh'sche Verlagshandlung, Stuttgart 1981, ISBN 3-440-04951-5 .
- Axel Hausmann: The Geometrid moths of Europe, 2nd Sterrhinae. Apollo Books, Stenstrup 2004, ISBN 8-788-75737-4
