The Elrhaz Formation is a geological formation in Niger, West Africa.

Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the formation, alongside those of multiple species of crocodyliformes.

Gadoufaoua (Tuareg for "the place where camels fear to go") is a site within the Elrhaz Formation (located at 16°50′N 9°25′E / 16.833°N 9.417°E / 16.833; 9.417) in the Tenere desert of Niger known for its extensive fossil graveyard. It is where remains of Sarcosuchus imperator, popularly known as SuperCroc, were found (by Paul Sereno in 1997, for example), including vertebrae, limb bones, armor plates, jaws, and a nearly complete 6 feet (1.8 m) skull.

Gadoufaoua is very hot and dry. However, it is supposed that millions of years ago, Gadoufaoua had trees, plants, and wide rivers. The river covered the remains of dead animals, the fossilized remains of which were protected by the drying rivers over millions of years.

Chondrichthyes
Genus	Species	Material	Notes	Images
Hybodus	H. sp.	Dorsal spines

Sarcopterygii
Genus	Species	Material	Notes	Images
Asiatoceratodus	A. tiguidiensis		Dipnomorph fish. Originally described as Ceratodus tiguidiensis, assigned to Arganodus by M. Martin (1984) and reassigned by Kemp (1998) to the genus Asiatoceratodus.
Mawsonia	M. tegamensis		A small species.
Neoceratodus	N. africanus	Tooth plates.	Dipnomorph fish. Originally described as Ceratodus africanus, assigned to Neoceratodus by M. Martin, 1982.

Actinopterygii
Genus	Species	Material	Notes	Images
Pliodetes	P. nigeriensis	Skull and postcranial material including body scales.	Originally thought to be a semionotid, later assigned to Lepisosteoidei.
Pycnodontidae indet.	Indeterminate

Testudines
Genus	Species	Material	Notes	Images
Francemys	F. gadoufaouaensis	"Shell of a juvenile individual and several articulated and disarticulated plates."	Pelomedusoid turtle. Named in honour of France de Lapparent de Broin.
Taquetochelys	T. decorata	A few disarticulated plates and nearly complete skeleton.	Araripemydid turtle, similar in shell size to South American Araripemys (20–30 cm). Laganemys tenerensis was synonymysed with Taquetochelys by Pérez-García, 2018.
Teneremys	T. lapparenti	"Several relatively complete skeletons."

Crocodyliformes
Genus	Species	Material	Notes	Images
Anatosuchus	A. minor	"Nearly complete skull"
Araripesuchus	A. wegeneri	"Nearly complete skull"
Sarcosuchus	S. imperator	"Partial skeletons, numerous skulls"
Stolokrosuchus	S. lapparenti

Ornithischians
Genus	Species	Material	Notes	Images
Elrhazosaurus	E. nigeriensis	"Femora."	A dryosaurid
Lurdusaurus	L. arenatus	"Partial skull, fragmentary postcranial skeleton."
Ouranosaurus	O. nigeriensis	"Skull and poscrania, second skeleton."

Theropods
Genus	Species	Material	Notes	Images
Afromimus	A. tenerensis	"caudal vertebrae, chevrons and portions of the right hind limb"	A Noasaurid
Carcharodontosaurus		Partial remains discovered 1976
Eocarcharia	E. dinops	"Partial skull and postcranial remains."	Carcharodontosaurid
Kryptops	K. palaios	Postcranial skeleton and partial skull.	Abelisaurid
Suchomimus	S. tenerensis	Partial skull and associated skeleton.	A second, spinosaurid found in the formation, Cristatusaurus, is considered either a separate species or a synonym to Suchomimus

Sauropods
Genus	Species	Material	Notes	Images
Nigersaurus	N. taqueti	Skull and skeletal remains	A rebbachisaurid.

• List of dinosaur-bearing rock formations
• Crato Formation
• Romualdo Formation

• Sereno, P. C.; Larsson, H. C.; Sidor, C. A.; Gado, B. (2001), "The giant crocodyliform Sarcosuchus from the Cretaceous of Africa", Science, 294 (5546): 1516–1519, Bibcode:2001Sci...294.1516S, doi:10.1126/science.1066521, PMID 11679634ISSN 0036-8075PMID 11679634
• Sereno, Paul C.; Brusatte, Stephen L. (2008), "Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger" (PDF), Acta Palaeontologica Polonica, 53: 15–49, doi:10.4202/app.2008.0102, retrieved 2018-10-06
• Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), The Dinosauria, 2nd edition, Berkeley: University of California Press, pp. 1–880, ISBN 0-520-24209-2, retrieved 2019-02-21

• P. M. Galton and P. Taquet. 1982. Valdosaurus, a hypsilophodontid dinosaur from the Lower Cretaceous of Europe and Africa. Géobios 15(2):147-159
• H. C. E. Larsson and B. Gado. 2000. A new Early Cretaceous crocodyliform from Niger. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 217(1):131-141
• P. C. Sereno and S. J. ElShafie. 2013. A New Long-Necked Turtle, Laganemys tenerensis (Pleurodira: Araripemydidae), from the Elrhaz Formation (Aptian–Albian) of Niger. In D. B. Brinkman, P. A. Holroyd, J. D. Gardner (eds.), Morphology and Evolution of Turtles 215–250
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