Moschops

Here is the rewritten encyclopedia entry about **Moschops**:

**Moschops** (meaning "calf face" in Greek) is an extinct genus of dinocephalian therapsid from the Middle Permian, living roughly 264.4 to 260 million years ago in what is now South Africa. Its fossils come from the Tapinocephalus Assemblage Zone of the Abrahamskraal Formation. Like other tapinocephalids, Moschops was a heavily built herbivore. Its body mass has been debated; one 2017 study gave an average and maximum weight based on a regression formula, while a 2024 study estimated the mass of one specimen (SAM-PK-11972) using a 3D model, suggesting that method was more accurate. It has also been debated whether Moschops was semi-aquatic, like a hippopotamus. Its short, thick skull and robust build have led many to believe it engaged in head-butting contests with rivals of the same species.

The first Moschops material was found in the Karoo region of South Africa, on the Spitzkop farmstead north of Laingsburg, by Robert Broom and Reverend John Henry Whaits. Broom brought the specimens to the American Museum of Natural History in New York City in 1910. He initially thought the remains came from the Permian upper Ecca Group, based on the lack of pareiasaurs and a single tooth. That original collection includes a holotype (AMNH 5550) and seven topotypes (AMNH 5551–5557). The skulls show varying degrees of pachyostosis, which Broom linked to differences in sex and age. Later researchers determined the fossils actually came from the Tapinocephalus Assemblage Zone, dating to the Middle Permian.

Moschops had a short, broad, massive head, especially wide around the eye sockets. The rear of the skull was deep, but it became shallower and broader toward the front. Like other dinocephalians, the eye sockets are ringed by swollen, thickened bone—the feature that gives the group its name. These bony bosses do not resemble the antlers or horns of modern mammals; instead, they are similar to thickened bone patches seen in some toothed whales, like bottlenose whales. Synchrotron scanning of one *M. capensis* skull suggests neurological adaptations for intense head-to-head combat. The occiput was broad and deep, providing attachment for powerful neck muscles. The pterygoid arches were heavy, and together with the angular bone of the lower jaw, the pterygoid muscles were likely very strong. Like other dinocephalians and non-cynodont therapsids, the skull roof had an opening for a parietal eye, a light-sensitive organ that helps regulate circadian rhythms and body temperature.

The vertebrae of Moschops are holospondylous—the bones are fused. It appears to have had 29 presacral vertebrae and three sacral vertebrae, though the exact number is uncertain. The neck curved upward, but less strongly than in the related *Moschognathus*. The cervical vertebrae were shorter, especially the axis. The cervical ribs attached low on the centra, below the zygapophyses. The front dorsal vertebrae are larger than the rear ones, reflecting the size difference between the shoulder and hip. Each dorsal vertebra is heavily built, short from front to back, and wide from side to side, with flattened front and back faces (amphiplatyan). The lumbar vertebrae are much thinner. No tail vertebrae from the very end are known, but the front tail bones and rear sacrals are large, suggesting a tail of moderate length. Ribs are present on every vertebra from the atlas to the last known tail vertebra. Most ribs resemble those of basal synapsids, but the first sacral rib is exceptionally large and may have helped support the pelvis.

Moschops likely had a semi-erect gait. Its shoulder and hip girdles are intermediate in form between those of basal synapsids (like pelycosaurs) and more advanced therapsids.