Figure 4 from: Ichiishi W, Shimada S, Motobayashi T, Abe H (2019) Completely engaged three-dimensional mandibular gear-like structures in the adult horned beetles: reconsideration of bark-carving behaviors (Coleoptera, Scarabaeidae, Dynastinae). ZooKeys 813: 89-110. https://doi.org/10.3897/zookeys.813.29236

Figure 4 Mandibles of T.dichotomus adults. A A male adult viewed from the left side with a ruler B lateral view of the head from the left side; the clypeus and mandible are indicated by arrows. Antenna and maxillary palp parts were removed to expose the mandible C diagram of the head; the mandible is indicated by a stipple D a head before removing the mandible E a head after removing the mandible F the left side mandible was dissected from the cranium G diagram showing the double articulation of the mandible; the right side diagram is of the cranium H a left side mandible of T.dichotomus with attached muscles. Abbreviations: add = adductor muscle; abd = abductor muscle; d = dorsal articulation (socket); v = ventral articulation (condyle). Scale bar: 1 mm.