basic conical forms to leaf-like shapes with large serrations. These are probably indicative of an omnivorous or herbivorous diet, and similar adaptations are seen in other archosaurs with less reliance on meat in their diet. A few aetosaurs have teeth with a ziphodont shape, meaning that the teeth are recurved, serrated, and flattened from the side. This shape, which is predominant in Aetosauroides and a small specimen tentatively referred to Coahomasuchus, is typical of carnivorous archosaurs. In some aetosaurs (particular members of the group Desmatosuchia), the tip of the snout is expanded sideways into a flattened 'shovel' shape, akin to the snout of a pig. The external nares (nostril holes) are elongated, much larger than the antorbital fenestrae (a hole on the side of the skull). Many aetosaurs have a small knob on the premaxilla which projects into the nares from below. In all aetosaurs except Aetosauroides, the rear edge of the naris receives a contribution from the concave front edge of the maxilla bone. At the rear upper part of the skull, a hole known as the supratemporal fenestra is positioned and exposed on the side, unlike most other archosaurs where it is mostly visible when viewing the skull from above. The braincase is fairly standard by pseudosuchian standards, though the opening for the abducens nerve passes through the parabasisphenoid bone (at the lower front part of the braincase), rather than the prootic bone (at the upper front part). This trait is otherwise only seen in Revueltosaurus and crocodylomorphs among archosaurs. The mandible (lower jaw) is described as 'slipper'-shaped in many aetosaurs. This is due to a combination of features: the front of the dentary strongly tapers to a point, while the underside of the dentary sometimes flexes into a 'chin' (downwards projection) which may expose the splenial bone as well. The jaw joint is set at a low position, and the articular (the bone of the lower jaw which connects to the cranium) often has a tall projection right behind the jaw joint. Postcranial anatomy In most respects apart from their skull and armor, the skeletal anatomy of aetosaurs was fairly standard among other large Triassic pseudosuchians. The hindlimbs developed a "pillar-erect" limb posture similar to that seen in "rauisuchians", a related grade of carnivorous Triassic pseudosuchians ancestral to crocodylomorphs. A pillar-erect limb posture is one where the femur articulates vertically with the acetabulum of the hip, which