Minotaur beetles grow to 15 to 24 mm in length. Their bodies are black and slightly shiny all over, stout and dome-shaped. On the elytra are longitudinal grooves with punctures. There are numerous small spines on each leg. The species clearly exhibitssexual dimorphism. Characteristic of the males are three horn-like outgrowths on the pronotum. The two outer protrusions are long, while the one in the middle is short. The females instead have a few pointed humps here.