Quilmesaurus belongs to the family of theropod dinosaur that had been found existed in the Late Cretaceous period, over 80-70 million years ago. The fossil remains of the species were first discovered in Woodlands of South Africa especially in south of Roca City, in Río Negro and near the Salitral Ojo de Agua. This carnivore species comes under the classification of Chordate, Dinosauria, Theropoda, Abelisauridae, Carnotaurini.
The species was first named and described by Rodolfo Aníbal Coria in 2001. The preserved holotype, MPCA-PV-100 is the known part of collection of this species that consists of the distal, lower, half of the right femur, thighbone, and a complete right tibia. From the identified fossil specimen it has been observed that the dinosaur was about 20 feet in length and 1,000 pounds in weight. Its unique distinguishing characteristics include bipedal posture and stunted arms. The femur has a well developed mediodistal and hatchet-shaped cnemial crest.