Lucanus cervus is 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. L. cervus is situated in the genus Lucanus within the family Lucanidae. In the genus there are two subgenera: Lucanus Scopoli, 1763 and Pseudolucanus Hope and Westwood, 1845. The species L. cervus contains four subspecies. The nominate subspecies L. cervus cervus (Linnaeus, 1758) was established via the original description of the species in 1758. The three latterly added subspecies are L. cervus judaicus Planet, 1900, L. cervus laticornis Deyrolle, 1864, and L. cervus turcicus Sturm, 1843. 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 horns 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. L. cervus is widespread across Europe, though it is absent from Ireland. In Germany it is widespread, mainly in the south. In Hungary this species is widespread in the hilly and mountainous areas. In Romania it is widespread, especially in the hilly areas with sun exposed slopes. It also occurs in the European part of Turkey. In Italy it is mainly distributed in northern and central regions. In Spain and Portugal it is present only in the northern half of each country. In Britain it is largely confined to the south-east of England, where it is widespread. This species is now extinct in Denmark and Latvia. It is also found in Caucasus, Asia Minor, Syria and west Kazakhstan. Its range is currently only increasing in Croatia and Slovakia. L. cervus has been associated with a range of trees including those in the families oak (Quercus), lime (Tilia), beech (Fagus), willow (Salix) and certain species in other families including black poplar (Populus nigra), ash (Fraxinus excelsior), horse-chestnut (Aesculus hippocastanum), wild cherry (Prunus avium), and common walnut (Juglans regia). Larval development sites were found in proximity of dead wood of the allochthonous Quercus rubra. Adults appear during late May to the beginning of August, being most active in the evenings. Females lay their eggs in a piece of decaying wood deep in the soil. Stag beetle larvae, which are blind and shaped like a letter 'C', feed on rotting wood in a variety of places, tree stumps, old trees and shrubs, rotting fence posts, compost heaps, and leaf mould. The larvae have a cream-coloured, soft, transparent body with six orange legs, and an orange head which is very distinct from the very sharp brown pincers. They have combs in their legs which they use for communication (stridulation) with other larvae. The larvae go through several instar stages, taking 4 to 6 years to become pupae. The work of entomologist Charlie Morgan during the late 1970s discovered that the pupae of the stag beetle live in the soil for about 3 months, then emerge in summer to awkwardly fly off to mate. Adults only live for a few weeks, feeding on nectar and tree sap. Their slow, lumbering flight, usually at dusk, makes a distinctive low-pitched buzzing sound. The males fly more readily than the females.