The "major" males of this species have three large horns on their thoraces, resembling Triceratops.

The female ox beetle has a very short horn which has little use in fighting, but is used for digging in the ground.

These beetles grow to about 1.0 to 1.5 in (2.5 to 3.8 cm) long as adults when the horns are excluded in the males.

The pupal stage can be shortened in captivity by placing the pupae in a warm area.

These beetles are very common near lights in the summer and can be collected in large numbers in some areas.