A Visit To a Big Stag Beetle
Let me introduce myself!
My name is a stag beetle (the scientific name Lucanus cervus) and I am a giant among the bugs. I can grow up to 85 mm in length, so I'm the biggest beetle in Europe. You can best recognize me by the huge mandibles that resemble the horns of a stag. But they are not dangerous. I use them only in conflicts with other males when I want to win a female. With this mandibles, I grab an annoying bug, and I wrestle with it for as long as I do not turn it on his back! I'm too clumsy to pinch you. You can be pinched by a female who also uses her powerful mandibles to bite the bark on the old trees. From the cracks in the bark then comes the sweet plant juice with which we feed.
My family
My larvae come out of the eggs, which the female lays in the decaying wood of dead trees, roots or decaying wood residues in the soil. C shaped larvae with orange head and strong mandibles for 3 to 6 years drill down to decaying wood and feed with it. They have combs in their legs which they use for communication, stridulation, with other larvae.
When the larvae are large enough, they become pupae for two months. In autumn, larvaes transforme, and adult males or females wait until the late spring when we bite out of the chamber in the ground and fly off. We fly and loudly rush through the forest in the evening from May to August, but we live only for three weeks.

Mature larva

Male pupa

The life cycle of a stag beetle(design: Maria Fremlin, illustrations: Carim Nahaboo)
Where do I live?
I prefer old, thick trees of oak, chestnut, ash and other deciduous trees. As the old thick trees in European forests, parks and gardens are becoming less and less, I belong to endangered species. The city of Ljubljana is one of the few European capitals, where I find enough old thick trees to live in them with my family. If you notice adult males or females of the stag beetle bug, report to the web portal The Institute of the Republic of Slovenia for Nature Conservation or the The European Stag Beetle Monitoring Network. This way, you will learn more about our way of life and better protect our living space.
Resources
Evropski svet (19.9.1979) Appendix III - Protected fauna species. Convention on the Conservation of European Wildlife and Natural Habitats.
Location inventory, The Institute of the Republic of Slovenia for Nature Conservation, http://www.sporocivrsto.si/web/profile.aspxid=ZRSVN_hrosci@Slo http://maria.fremlin.de/stagbeetles/index.html
"Lucanus cervus". The IUCN Red List of Threatened Species. 2017. Retrieved 2017-01-23. Harvey, D.J.; Gange, A.C.; James, C. J.; Rink, M (2011). "Bionomics and distribution of the stag beetle, Lucanus cervus (L.) across Europe". Insect Conservation and Diversity. 4: 23–38.