Anteosaurus

Anteosaurus (meaning "previous or early reptile") is the name given to an extinct genus of large carnivorous mammal-like reptile. It lived during the Capitanian epoch of the Middle Permian (266-260 million years ago) in what is now South Africa. They became extinct by the middle Late Permian. Anteosaurus is a semi aquatic reptile with a long tail and weak limbs, which indicate a lifestyle including water, much like that of a crocodile. They are mainly carnivorous, but some have been known to be herbivorous or omnivorous. Anteosaurus weighs approximately 500-600 kg and is around 5-6 m in length. Its most notable characteristic is its tall, narrow skull, which is 80 cm long. The size of the skull is used to determine the age of a fossil. The teeth are another identifying characteristic of Anteosaurus. The teeth on the roof of the mouth are enlarged and confined in a cluster near the outer tooth row. The "normal teeth" include the anterior, canine and cheek teeth. A prominent feature of the Dinocephalians is the ledge on the anterior teeth. The canine teeth are big, and there are usually about 10 cheek teeth present. The front of the mouth curves up due to the premaxillary bone of the upper jaw. Paleontologists believe the presence of Pachytosis (thickening of the roof of the head) indicates a "head-butting" behavior of these dinocephalians, probably for protecting territory and fighting over a mate. This feature indicates that they were active on land as well.

Discovery
The skull of a young Anteosaurus was found in Eastern Cape Province, South Africa where many skull fragments have been discovered relating to the dinocephalians. While 4 other Anteosauridae were found in the Isheevo region, the Anteosaurus was the only Anteosauridae predator in the South African temperate zone.

Related species
The ancestors of Early Therapsids from the late Permian include Strathiocephalus and Tapinocaninus. These Therapsids are classified by their skull pachyostosis, body size, and herbivory. There are six other genera of the Tapinocephalus which are related to Anteosaurus: Eccasaurus, Titanognathus, Dinosuchus, Micranteosaurus (considered a "young" anteosaurus because of its small size) and Pseudanteosaurus. There are 16 well-preserved skulls of Anteosaurus, 10 of which have been named as species of Anteosaurus, and are distinguished by their skull size and shape, number size and shape of teeth. The primitive skull and canine teeth are a distinctive characteristic of the Anteosaurus, which were passed on to its later descendants such as the Titanosuchidae, which replaced most eating habits into herbivory. The giant Anteosaurus is known to have existed at the same time that the Titanophoneus and Doliosauriscus dominated in the Isheevo region. The Anteosauridae family replaced the Eotitanosuchidae, but they (the Anteosauridae) were replaced by large Gorgonopsids.