Common dwarf beetle
| Common dwarf beetle | ||||||||||||
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Common pygmy beetle ( Trachys minutus ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Trachys minutus | ||||||||||||
| Linnaeus , 1758 |
| Pictures of Trachys minutus Fig. 4–7 according to Reitter |
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| Image 1: side view | Image 2: from below | Image 3: front view |
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Image 4: chin, tongues, lip switch |
Fig. 5: Maxilla with jaw palpation | Image 6: Underside of larvae head |
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| Photo 7: larva | ||
The Common dwarf jewel beetle , also Hardwood small jewel beetle , ( trachys minutus ) is a beetle of the family of jewel beetle and the subfamily of Agrilinae . It becomes 3 to 3.5 millimeters long. It has a dark ore-colored shine and is sparsely haired in white.
Like almost all jewel beetles, the species is specially protected by law in accordance with the Federal Species Protection Ordinance. It is classified as endangered nationwide and in Baden-Württemberg . In Rhineland-Palatinate it is considered to be highly endangered , in Brandenburg and Schleswig-Holstein it is on the warning list as potentially endangered . In Saxony-Anhalt it is threatened with extinction.
Comments on the name and system
The species is first described by Linnaeus in 1758 under the name Buprestis minuta . The small size is not mentioned in the description, which consists of only nine words, but the species name minūta ( Latin for tiny) refers to the size, which is unusually small for jewel beetles.
The genus Trachys is established by Fabricius in 1801 . In the detailed Latin characterization of the genus, the description of the wing coverts begins with the words: elytris rigidis (Latin for rough wing coverts). This explains the generic name Tráchys ( old Gr . Τραχύς trachýs, rough).
The genus Trachys is represented in Europe with twenty species. There are over six hundred species worldwide.
description
The dwarf jewel beetles are not only characterized by their small size, but also by their unusually wide shape for jewel beetles, reminiscent of a leaf bug.
The head (Fig. 3) is broad, the forehead and crown are clearly angled to rounded. The leading edge of the large eyes runs along the edge of this impression. The upper lip is cut out and eyelashed in front. The upper jaws are short, thick, curved, with a blunt tooth on the inner edge. The jaw buttons (Fig. 5) are thickened to form a club, the second link long, the fourth spherical egg-shaped. The lip switch end link is small and truncated in a spherical shape (Fig. 4) The eleven-link feelers are short, the first two links are thickened, the last five are widened inwards (sawn).
The pronotum is widest at the base and tapers rapidly towards the front. Its rounding is continued by that of the slightly sunken head. The pronotum has no dimple and no impression at the front angle. At the base, the pronotum in front of each wing cover is doubly bulged towards the front, and widened in an arched manner towards the triangular plate towards the rear (Fig. 3).
The scutellum is very small and round. The wing covers show a clearly protruding shoulder bulge at the base. The shoulders are a little wider than the base of the pronotum. The sparse white basic hair is inconspicuous. The wavy bands of longer white hair can be rubbed off, the rear ones are most clearly formed. In rare cases, metallic colored animals appear.
The front hip cavities are open at the back, the front hips spherical, separated by a broad extension of the front chest (prosternal extension). It continues over the narrow mid breast to the rear breast (Fig. 2). The rear hips lie broadly against the rear chest and are hollowed out to partially accommodate the hind legs. The tarsi each have five limbs that are short, triangular and tomentose on the underside. The claws are toothed
The first two of the 5 sternites have grown together.
Occurrence
The species is found in deciduous forests in Europe , Asia Minor , Siberia and in the Caucasus and as far as Japan . It is considered to be a Siberian element of fauna that shines westward as far as Spain .
The animals do not make any special demands on the habitat, they can be found in moist alluvial forests and moors as well as on dry slopes.
Way of life
The animals overwinter as adults . To do this, they look for protected places, for example in the moss. They appear in early spring, for example, they can be found in the flood crest. The beetles sit on the leaves of the host plants, which they gnaw on the edge.
Willow and hazel are common among the many very different host plants . The latter is mentioned as the host plant of the species (lat. Habitat in Corylo) in Fabricius 1801.
The female lays the eggs on the hairy leaves of deciduous trees. You choose trees in a sunny location. Eggs are preferably laid on the upper side of the leaf on the slightly downwardly curved leaf tips and is continued in Central Europe from early spring to autumn. Each egg is individually covered with a black putty. The larvae (Fig. 6 and 7) eat the green parenchymal tissue between the upper and lower covering layers of the leaves. The resulting cavities (mines) appear glassy or lighter green due to the lack of leaf green. Since the areas eaten empty are not corridors, but rounded areas, they are called space mines.
The development to the finished beetle takes one to almost two months. There may be several generations each year.
swell
literature
- Fritz Brechtel, Hans Kostenbader (ed.): The splendor and stag beetles of Baden-Württemberg. Eugen Ulmer, Stuttgart 2002. ISBN 3-8001-3526-4
- Jiři Zahradnik, Irmgard Jung, Dieter Jung, Jarmila Hoberlandtova, Ivan Zpevak: Beetles of Central and Northwestern Europe. Parey, Berlin 1985. ISBN 3-490-27118-1
- Heinz Joy, Karl Wilhelm Harde, Gustav Adolf Lohse: The beetles of Central Europe . tape 6 : Diversicornia . Spectrum, Heidelberg 1979, ISBN 3-87263-027-X .
- G. Jäger (editor): CG Calwer 's Käferbuch . K. Thienemanns, Stuttgart 1876, 3rd edition
- Adolf Horion: Beetle science for nature lovers. Vittorio Klostermann, Frankfurt am Main 1949.
Individual evidence
- ↑ Edmund Reitter : Fauna Germanica, the beetles of the German Empire III. Volume, KGLutz 'Verlag, Stuttgart 1911, plate 120
- ↑ a b Trachys minutus in Fauna Europaea. Retrieved March 27, 2013
- ↑ Red lists at BioNetworkX ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ↑ Fritz Brechtel, Hans Kostenbader (ed.): The splendor and stag beetles of Baden-Württemberg , Eugen Ulmer Verlag Stuttgart 2002, ISBN 3-8001-3526-4
- ↑ C.Linnaeus: Systema Naturae per Regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata Stockholm 1758 first description page 410 no.17
- ↑ Sigmund Schenkling: Nomenclator coleopterologus 2nd edition Jena 1922 Explanation of the scientific beetle names (species) in short form
- ↑ a b Joh. Chr. Fabricius: Systema Eleutheratorum 2nd vol. Kiel 1801 Characterization of the genus p. 218
- ↑ Sigmund Schenkling: Nomenclator coleopterologus 2nd edition Jena 1922 Explanation of the scientific beetle names (genus) in short form
- ↑ Trachys in Fauna Europaea. Retrieved March 27, 2013
- ↑ Species of the genus Trachys at BioLib
