The English name is derived from the large and distinctive mandibles found on the males of most species, which resemble the antlers of stags.

Because its mandibles are capable of exceeding its own body size, stag beetles are generally inefficient runners and are very slow, and typically feel the need to fly from one location to another.

In the final larval stage, "L3", the surviving grubs of larger species, such as Prosopocoilus giraffa, may be the size of a human finger.

In England’s New Forest, it was once believed that the stag beetle, dubbed the "devil's imp", was sent to do some evil to the corn crops.

[5][6] The oldest known fossil of the group is Juraesalus from the late Middle Jurassic (Callovian) Daohugou Beds of Inner Mongolia, China.