Lucanus datunensis is a stag beetle that is endemic to Taiwan. It has a narrow distribution, only found in the Datun mountain area of Yangmingshan National Park. The females of this species are extremely crptic with very few sightings. Since its discovery in 1984, little is known about its ecology and life history. This image of a mating pair captured on Usawa cane provides a rare reproductive record in their habitat.