Japanese Giant Stag Beetle

Dorcus is a large genus of stag beetles in the subfamily Lucaninae, comprising over 100 species distributed primarily across Asia and India, with two species in Europe and two in North America. These beetles inhabit deciduous forests, where larvae develop inside decaying hardwood logs. Males possess powerful, flattened mandibles used in competition for mates and feeding sites, with body lengths ranging from 30–90 mm depending on species. Adults are glossy black and have notably long lifespans of one to three years compared to many other beetles. In captivity, small to medium enclosures with ventilated lids are suitable. Egg-laying occurs inside hardwood logs such as oak, and larvae thrive in fungal substrate bottles, which can produce exceptionally large specimens. Their long adult lifespan and moderate care requirements make Dorcus beetles highly popular among collectors.

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Jelly (adult) / Fungus bottle (larva)