abelisaurid

Abelisauridae is a family of predatory theropod dinosaurs within the larger Ceratosauria, known from the Jurassic to the Late Cretaceous. Fossils have been found primarily in Gondwanan landmasses, including South America, Africa, Madagascar, India, and possibly Antarctica, indicating a widespread southern-hemisphere distribution. The group's earliest known member, Eoabelisaurus mefi from the Early Jurassic of Patagonia, suggests an early origin for the lineage.

Abelisaurids typically have short, high skulls with ornamented bones and often display horns, crests, or bosses on the snout and cheek regions. They are notable for very short forelimbs, usually with two tiny digits, as seen in Carnotaurus. The hind limbs are strong and the teeth are blade-like, consistent with a carnivorous diet.

Several well-known genera illustrate the group's diversity. Carnotaurus sastrei from Argentina is famous for its extremely reduced arms and horned skull. Majungasaurus crenatissimus from Madagascar shows a tall, crested skull and is among the best-documented abelisaurids from that region. Rugops primus from Africa and Indosuchus from India are other examples, with Viavenator exxoni from Argentina representing a more recently described South American form.

Classification places Abelisauridae within Abelisauroidea of Ceratosauria. Relationships within the group have varied as new fossils are found, with proposed subdivisions such as Carnotaurinae and Majungasaurinae. Abelisaurids occupied mid- to large-sized predator niches and coexisted with other theropods in some ecosystems. The lineage declined toward the end of the Cretaceous, with the last members appearing in the late Cretaceous fossil record.