| Named By: | Coria & Salgado in 1998 |
| Time Period: | Late Cretaceous, 95 Ma |
| Location: | Argentina, Neuquen Province - Rio Limay Formation |
| Size: | Roughly estimated about 6-7 meters long |
| Diet: | Carnivore |
| Fossil(s): | Fragmentary skull and partial post cranial remains |
| Classification: | | Chordata | Reptilia | Dinosauria | Saurischia | Theropoda | Abelisauridae | Carnotaurinae | Brachyrostra | |
Ilokelesia is an abelisaur found in 1991, preserved in the layers of the earliest Late Cretaceous of the Rio Limay Formation, Neuquen Group, located near Plaza Huincul, Neuquen Province, Argentina. The specimen, consisting of very fragmentary elements of the skull and the axial and appendicular skeleton, was described by Coria et al. in late 1998.
The generic name's etymology is derived from the Mapuche language, ilo meaning "flesh" and kelesio, "lizard"; while the specific descriptor reflects the name of the locality where the fossil was found, Aguada Grande.
Ilokelesia, a medium-sized theropod measuring 5.3 metres (17 ft) in length, is characterized by features of the skull, namely of the quadrate and postorbital bones. The vertebral series also has distinctive characters setting it apart from other abelisaurs, such as reduced processes on the cervical vertebrae and dorsal vertebrae lacking pleurocoels.
I. aguadagrandensis was considered the most basal abelisaur described at the time, sharing characters, such as an expansion of the postorbital bone above the orbit and a flange of the same bone inside the orbit, with Abelisauridae and Noasauridae; but it was considered to retain primitive features for Abelisauria, such as an opening in the quadrate bone and a T-shaped postorbital. A subsequent analysis has placed it within Abelisauridae, as a brachyrostran carnotaurine.