''Ilokelesia'' is an extinct genus of
abelisaurid
theropod,
[Coria, R.A.; Salgado, L. & Calvo, J.O. (1991) "Primeros restos de dinosaurios Theropoda del Miembro Huincul, Formación Río Limay (Cretácico Tardío Presenoniano), Neuquén, Argentina." '']Ameghiniana
''Ameghiniana'' is a peer-reviewed scientific journal covering palaeontology published by the Asociación Paleontológica Argentina. It is named after the 19th century Italian Argentine palaeontologist Florentino Ameghino. The discovery of many di ...
'', 28: 405-406. preserved in the layers of the
earliest Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...
of the
Huincul Formation, Neuquén Group, located near Plaza Huincul,
Neuquén Province
Neuquén () is a province of Argentina, located in the west of the country, at the northern end of Patagonia. It borders Mendoza Province to the north, Rio Negro Province to the southeast, and Chile to the west. It also meets La Pampa Province a ...
,
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
. The specimen, consisting of very fragmentary elements of the skull and the axial and appendicular skeleton, was described by
Rodolfo Coria and
Leonardo Salgado
Leonardo Salgado is an Argentinean palaeontologist with a special interest in dinosaurs of the Cretaceous period and other investigations of the palaeobiology of fossil bearing geological formations. Salgado is the leading or coauthor of several t ...
in late 1998.
Discovery and naming
''Ilokelesia'' is only known from very fragmentary elements of the skull and the axial and appendicular skeleton, discovered in 1991.
It was discovered ten meters away from where the holotype of ''
Huinculsaurus
''Huinculsaurus'' (meaning "Huincul Formation lizard") is a genus of noasaurid dinosaur from the Huincul Formation in Neuquén Province, Argentina. The type and only species is ''Huinculsaurus montesi''. It was probably around when fully grown, ...
'' was discovered. The genus was named and described in 1998.
Etymology
The generic name's etymology is derived from the
Mapuche
The Mapuche ( (Mapuche & Spanish: )) are a group of indigenous inhabitants of south-central Chile and southwestern Argentina, including parts of Patagonia. The collective term refers to a wide-ranging ethnicity composed of various groups who sha ...
language, ''ilo'' meaning "flesh" and ''kelesio'', "lizard"; while the specific descriptor reflects the name of the locality where the fossil was found, Aguada Grande.
Description
''Ilokelesia was'' a medium-sized
theropod. In 2010
Gregory S. Paul gave a length of 4 meters (13 ft) and a weight of 200 kg (440 lbs). In 2016 it was estimated to be in length in a comprehensive analysis of abelisaur size. The same year another estimation listed it higher at 5.8 meters (19 ft) and 840 kg (1,850 lbs).
It 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
Abelisauroidea is typically regarded as a Cretaceous group, though the earliest abelisauridae remains are known from the Middle Jurassic of Argentina (classified as the species Eoabelisaurus mefi) and possibly Madagascar (fragmentary remains of ...
, 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.
See also
*
Timeline of ceratosaur research
This timeline of ceratosaur research is a chronological listing of events in the history of paleontology focused on the ceratosaurs, a group of relatively primitive, often horned, predatory theropod dinosaurs that became the apex predators of ...
References
{{Taxonbar, from=Q135101
Brachyrostrans
Late Cretaceous dinosaurs of South America
Cenomanian life
Cretaceous Argentina
Fossils of Argentina
Huincul Formation
Fossil taxa described in 1998
Taxa named by Rodolfo Coria