Zygomatic bone

The zygomatic bone is a flat bone of the face, forming part of the latero-ventral orbital margin and the zygomatic arch. Its conformation can vary greatly depending on the species.

Despite great specific variation, this bone can be described as having a convex lateral surface, smooth and widened towards its rostral part, which can be crossed more or less close to its ventral edge by the facial crest, and a orbital surface that partly forms the ventro-lateral wall of the orbit, with a part of this surface opening onto the temporal fossa, and towards its rostral part, the orbital surface has a wide surface that joins with the maxilla. This bone also has a dorsal border, which forms part of the infraorbital margin and part of the dorsal border of the zygomatic arch, and a ventral border, which is largely free and joins the maxilla on its most rostral part.

Rostrally, this bone extends in front of the orbit, where it joins the maxilla and in particular the zygomatic process. It also joins the lacrimal bone, with which it forms the infraorbital margin. Caudally, the temporal process joins the zygomatic process of the temporal bone, with which it connects via an oblique bevel to form the zygomatic arch that defines the temporal fossa. In some species, a frontal process projects towards the zygomatic process of the frontal bone, and they may join or be completed by the orbital ligament, notably in carnivores and pigs.