Lucanus cervus

Lucanus cervus, known as the European stag beetle, or the greater stag beetle, is one of the best-known species of stag beetle (family Lucanidae) in Western Europe, and is the eponymous example of the genus. L. cervus is listed as Near Threatened by the IUCN Red List. 

Sexually dimorphic, the males have enlarged mandibles and are larger than the females. Although the male's mandibles seem threatening, they are too weak to be harmful. Nevertheless, females can inflict a painful bite. The resemblance of the male's mandibles to the antlers of a stag, and their use in combat between males, much like with deer, gives the species its scientific and common names.

Adult size varies between different areas of its distribution, for example beetles from Spain, Germany, and the Netherlands are larger than those from Belgium or the UK.

Lucanus cervus is listed as Near Threatened by the IUCN Red List. Although this species is widely distributed in Europe, it is in significant decline in the north and central part of its range and future trends of European forests will pose serious threats to this species, thus making the species close to qualifying for Vulnerable.

Lucanus cervus is registered in the second appendix of the Habitats Directive of the European Union from 1992, which requires that member states set aside special areas of conservation. The species is also registered in the third appendix of the Convention on the Conservation of European Wildlife and Natural Habitats (Berne convention) of 1982 and Schedule 5 of the UK's Wildlife and Countryside Act 1981.