Sulcophanaeus imperator

Adults of Sulcophanaeus imperator are 18–28 mm (0.7–1.1 in) long. Males have a dark, long and curved horn on the forehead, whereas females at most have a small indication of a horn. There are three distinct subspecies (or color phases) that are similar, except for their color. All three have a black center of the head and a large black spot on the central pronotum, while the central and frontal parts of the elytra are shiny blue, shiny green or black. In S. i. imperator ("golden phase") the outer parts of the head and outer and rear parts of the pronotum are gold to coppery, often with some shiny green, and the rear part and outer edges of the elytra are gold, coppery or shiny green. In S. i. alticollis ("red phase") the outer parts of the head, outer and rear parts of the pronotum, and the rear part and outer edges of the elytra are shiny coppery red to brick red. In S. i. obscurus ("green phase") the outer parts of the head, outer and rear parts of the pronotum, and rear part and outer edges the elytra are shiny green.

This species can be found in central to northwestern Argentina, central and southern Bolivia and western Paraguay in dry and thorny forests, pastures and scrublands at an elevation of 320–3,000 m (1,050–9,850 ft) above sea level.