Large species (25-40mm) with very marked sexual dimorphism ("male with a horn erect on the forehead flared in a trident at the apex, pronotum strongly excavated in front", PAULIAN loc. cit.).

3 ssp. identified, s.str. in the Loyalty Islands (nominative form of Lifou, capture of RP. Montrouzier, caledonicus Pell, 1933, the largest, on Grande Terre, and pinetorum Paulian, 1991 from the Isle of Pines.

Larvae in different types of soil, from decomposed wood to dead leaves.

Twilight or nocturnal adults, often attracted to lights.