Violet-necked snapback beetle
| Violet-necked snapback beetle | ||||||||||||
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Violet-necked snapback beetle ( Limoniscus violaceus ) |
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| Scientific name | ||||||||||||
| Limoniscus violaceus | ||||||||||||
| ( Müller , 1821) |
The Violet Blue root collar beetle ( Limoniscus violaceus ) is a beetle from the family of beetles (Elateridae).
features
Beetle
The length of the mostly crepuscular, if not nocturnal, violet-necked snail beetle is ten to twelve millimeters. The black wing covers have a raised seam and a blue shimmer. Because of this blue shimmer, there is little risk of confusion with other click beetle species.
Larvae
The larvae called wireworms for click beetles are omnivores . Their enemies include real ground beetles ( Carabus ) and fly-killer fungi (Entomophthorales). When threatened, the larvae can secrete a toxin on their jaws. The color of the larvae is golden yellow with a kind of silky sheen. The ninth abdominal segment is tan . The small spines ("spinules") of the thoracic legs are in a more dense arrangement than in the larvae of the red-bellied rapid leaf beetle ( Athous haemorrhoidalis ). The tergites (back plates) of adult larvae are rather dense and regularly granular, which distinguishes the larvae from click beetle larvae of the genera Athous and Hemicrepidius . The final ninth segment has two extensions, the urogomphi , which in wireworms of the violet-blue root neck beetle are regularly granular and appear slightly swollen. The shape and surface structure of the Urogomphi can distinguish the larvae from other click beetle species such as the red-bellied rapid leaf beetle ( Athous haemorrhoidalis ), Athous campyloides , Hemicrepidius hirtus and Denticollis linearis , which can be found in the same tree.
Distribution and occurrence
The species occurs in Europe, but not in the extreme north and south. In Denmark the species is considered to be extinct, as it was last detected there at the beginning of the 20th century. The type specimen was described by the Odenbach pastor Philipp Wilbrand Jacob Müller around 1800 after a specimen discovered near Meisenheim in the Palatinate .
As a so-called jungle relic of the beetle colonized old stocks of hardwood , such as Common ash and beech trees in England (with flower visits, for example, the intervention leagues Hawthorn ), turkey oak , linden , ash and maple trees in Hungary , as well as book and rare oak in France . The total area in Europe on which violet-necked snapback beetles occur is estimated to be less than 500 km².
A single fossil record comes from a Gallo-Roman excavation in the northern French department of Calvados , which is dated to around 150 AD, where the violet-blue root neck beetle was discovered together with the tripple beetle ( Valgus hemipterus ).
The larva is on those dark sludge instructed at the living trees, for example by fungal infestation, weevils the genus Rhyncolus , the pastures Bock ( Rhamnusium bicolor ) and ants out forms where strain caves touch the ground. These very rare conditions severely limit the potential occurrence of habitats and their distribution is accordingly limited and fragmented. , For the way it does not matter whether the tree can be found in old forests or cultivated land with tree stumps with coppice . However, sludge is preferred with a certain, constant moisture (rather moist) and a certain, also constant temperature (rather warm). Pupation takes place from August to September, mating and oviposition were observed in England from April to June, in Poland towards the end of April / beginning of May. The larval development extends over a period of two years.
Hazard and protection
The International Union for Conservation of Nature and Natural Resources (IUCN) assesses the stock as endangered .
The beetle is listed as a “ species of community interest ” in Appendix II of the Fauna-Flora-Habitat Directive of the European Union . This means that the member states are obliged to set up programs of measures for their preservation and to designate special protected areas within the scope of Natura 2000 . The species occurs in the protected area "Serriger Bachtal and Leuk and Saar" in Rhineland-Palatinate and in five forest areas in Hesse . Overall, it is in Germany be only about ten localities of the kind in England three.
Synonyms
Until the genus was named Limoniscus in 1905 by the Austrian entomologist Edmund Reitter , the species was referred to as Limonius violaceus in scientific literature .
Web links
- Limoniscus violaceus at Fauna Europaea. Retrieved January 5, 2013
- Limoniscus violaceus inthe IUCN 2012 Red List of Threatened Species . Posted by: Méndez, Marcos; Dodelin, J .; Petrakis, Panos; Schlaghamerský, Jiří & Nardi, Gianluca, 2010. Retrieved January 7, 2013.
- Limoniscus vioalceus on biolib.cz (English / Czech)
literature
- Georg Möller, Reiner Grube, Ekkehard Wachmann : Beetles in and on the forest (Der Fauna-Käferführer; Volume 1). Fauna Verlag, Nottuln 2006, p. 110, ISBN 3-935980-15-9 .
Individual evidence
- ↑ a b c P. F. Whitehead: Current knowledge of the violet click beetle Limoniscus violaceus (PWJ Müller, 1821) (Col. Elateridae) in Britain . Proceedings of the second pan-European conference on Saproxylic Beetles, 2003 (English).
- ↑ Violet Click Beetle Species Action Plan . Posted on Worcestershire County website (no longer online).
- ↑ Limoniscus vioalceus in the Coleoptera Poloniae database (English / Polish)
- ↑ Species profile RLP
- ↑ Species profile Hessen ( PDF ; 2.08 MB)