page_title: Eoabelisaurus
section_title: Description
hierarchical_section_title: Eoabelisaurus / Description
caption_attribution_description: English: Life restoration of Eoabelisaurus mefi
context_page_description: Eoabelisaurus is a genus of abelisaurid theropod dinosaur from the Middle Jurassic Cañadón Asfalto Formation of the Cañadón Asfalto Basin in Argentina, South America. The generic name combines a Greek ἠώς, "dawn", with the name Abelisaurus, in reference to the fact it represents an early relative of the latter. Only one species is currently recognized, E. mefi, from which the specific name honours the MEF, the Museo Paleontológico "Egidio Feruglio", where discoverer Diego Pol is active. It is characterized by reduced forelimb proportions that show primitive characteristics of the Abelisauridae family.
context_section_description: It was a bipedal carnivore that was estimated to have reached 6–6.5 metres (19.7–21.3 ft) in length, although a comprehensive analysis of abelisaur size conducted in 2016 yielded a size estimate of 5.8 metres (19 ft).  Molina-Pérez and Larramendi gave a higher estimation of 7.5 meters (25.6 ft) and 445 kg (981 lbs). The holotype specimen, MPEF PV 3990, was uncovered in a layer of the Cañadón Asfalto Formation, a lacustrine deposit dating from the Aalenian-Bajocian, roughly 170 million years old. It consists of a nearly complete skeleton with skull, of a subadult or adult individual.
  The posterior half of the skeleton was found in articulation and the anterior dorsal and cervical vertebrae and forelimbs were found partially disarticulated prior to burial. The skull was discovered slightly separated from the vertebral column. The skull and anterior presacrals were also exposed at the time of discovery and had been partially been destroyed by erosion. From the material known of the snout, only a small fragment of the right maxilla has been recovered and shows that the interdental plates are fused, but not striated. The known posterior part of the skull is high, with an oval orbit and an enlarged infratemporal fenestra, similar to other ceratosaurs. The skull roof is not notably thickened and no cranial ornamentation is present.
  Both humeri from the known material are poorly preserved, but show primitive characters. The articular head is slightly rounded, but not a globular shape that is commonly seen in noasaurids and abelisaurids. The radius and ulna are short and the ulna has a large olecranon process. The manus is very foreshortened, retains four digits, and has short metacarpals. Metacarpal I is about half the length of metacarpal II and considerably more slender. The arm also bears a stout phalanx that is slightly longer than the metacarpal. The non-terminal manual phalanges are about as long as wide and lack any constriction between the articular ends, and manual unguals are reduced. It is these reduced limb proportions that demonstrate Eoabelisaurus was indeed a primitive abelisaurid.
  The exact number of vertebrae is unknown due to several gaps in the holotype's spine, but its cervical vertebrae are short and have two pneumatic foramina on either side of the centra. The length of vertebral centra remains constant over the preserved portion of the tail, but middle and posterior caudals are considerably lower.
caption: Restoration
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