Cyclommatus elaphus
Cyclommatus elaphus is a species of stag beetle in the family Lucanidae. It is known from Sumatra and Malaysia. It is also the largest species of the genus Cyclommatus and can grow up to a maximum of from the tip of the mandibles to the end of the abdomen.
Cyclommatus kirchneri and Cyclommatus truncatus from Sumatra were first described as subspecies of Cyclommatus elaphus but are now recognized as full species.