Fig. 1.
From: Integrating evolutionarily novel horns within the deeply conserved insect head

Head horns in Onthophagus species possess a variety of shapes, sizes, and number of projections, but are positioned predominantly in the posterior region of the head (blue highlight). Species shown are—top row: Onthophagus taurus, Onthophagus australis, and Onthophagus schwaneri, and bottom row: Onthophagus rangifer, Onthophagus atripennis, and Onthophagus multicornis