The Bahariya Formation (also transcribed as Baharija Formation) is a fossiliferous geologic formation dating back to the early Cenomanian, which outcrops within the Bahariya depression in Egypt, and is known from oil exploration drilling across much of the Western Desert where it forms an important oil reservoir.Weishampel, David B; et al (2004). "Dinosaur distribution (Late Cretaceous, Africa)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 604. .
Extent
The Bahariya Formation forms the base of the depression, the lower part of the enclosing escarpment and all of the small hills within. The type section for the formation is found at Gebel El-Dist, a hill at the northern end of the Bahariya depression.
Stratigraphy and sedimentology Four depositional sequences have been recognised in the Bahariya Formation in the Bahariya depression, separated by three sub-aerial unconformities. The formation was deposited during a period of relative rise in sea level, with each unconformity representing a relative fall in sea level. Each of the individual sequences contains sediments deposited under fluvial, shoreline and shallow marine conditions.
Microfauna and Meiofauna
Foraminifera
Foraminifera of the Bahariya Formation Genus Species Charentia C. cuvillieri Favusella F. washitensis Mayncina M. orbignyi Rotalipora R. cushmaniR. reicheli Thomasinella T. aegyptiaT. fragmentariaT. punica Whiteinella W. archaeocretacea
Other microorganisms
Other microorganisms of the Bahariya Formation Genus Species Images Botryococcus Coronifera C. oceanica Cyclonephelium C. edwardsiiC. vannophorum Dynopterigium D. cladoides Exochosphaeridium Florentinia F. cooksoniaeF. mantlii Kallosphaeridium Mudrongia M. simplex Palaeoperidinium P. cretaceum Pediastrum Pseudoceratium P. anaphrisumP. securigerum Scenedesmus Spiniferites Subtilisphaera S. perlucidaS. senegalensis Xiphophoridium X. alatum
Invertebrates
Molluscs Molluscs of the Bahariya Formation Genus Species Notes Images Baculites A heteromorph ammonite with a nearly straight shell. Cardium A cockle. Exogyra A reef-forming true oyster associated with solid substrates and warm temperatures. Gastrochaena A saltwater clam. Neolobites N. vibrayeanus A typical rolled ammonite. Nucula A small saltwater clam. Ostrea O. flabeata An edible oyster.
Crustaceans (Ostracoda) Crustaceans of the Bahariya Formation Genus Species Notes Images Amphicytherura A. sexta Anticythereis A. gaensis Bairdia B. bassiouniiB. elongata Brachycythere B. ledaforma porosa Bythoceratina B. avnonensisB. tamarae Bythocypris B. eskeri Cythereis C. algerianaC. bicornis levisC. canteriolata Cytherella C. ovataC. paenovataC. parallelaC. sulcata Fabanella Looneyella L. sohni Loxoconcha L. clinocostaL. fletcheri Metacytheropteron M. berbericum Ovocytheridea O. caudataO. productaO. reniformis Paracypris P. acutocaudataP. angustaP. mdaouerensisP. triangularis Pterygocythere P. raabi Veeniacythereis V. jezzineensis Xestoleberis X. obesa
Insects Direct fossils are sparse, though plant leaves with extensive damage from folivorous insects have been documented.
Vertebrates
Cartilaginous fish
Chondrichthyes of the Bahariya Formation Genus Species Abundance Notes Images Aegyptobatus A. kuehnei A sclerorhynchiform. Asteracanthus A. aegyptiacus A hybodont shark. Baharipristis B. bastetiae A sclerorhynchiform. Cretodus C. longiplicatus A shark. Cretolamna C. appendiculata A mackerel shark. Distobatus D. nutiae A sclerorhynchiform. Gymnura G. laterialata A butterfly ray. Haimirichia H. amonensis A shark previously classified in the genera Odontaspis, Serratolamna, and Carcharias. Isidobatus I. tricarinatus A sclerorhynchiform. Marckgrafia M. lybica A sclerorhynchiform. Onchopristis O. numida One complete cranium and associated vertebrae. A sclerorhynchid rajoid. Peyeria P. libyca A sclerorhynchiform. Ptychotrygon P. henkeli A sclerorhynchiform. Renpetia R. labiicarinata A sclerorhynchiform. Rhinoptera A batoid ray. Scapanorhynchus S. subulatus A mitsukurinid similar to the modern goblin shark. Schizorhiza S. stromeri Specimens are actually from the younger Ain Giffara Formation. Squalicorax S. baharijensisAbundant. A large shark. Squatina An angelshark. Tribodus T. aschersoni A hybodont.
Bony fish Osteichthyes of the Bahariya Formation Genus Species Abundance Notes Images Bawitius B. bartheliA skull fragment, teeth, and several scales. A giant bichir. Ceratodus A lungfish. Coelodus A pycnodontid. Enchodus One tooth. A predatory fish. Lepidotes Isolated scales. Possibly misidentified from Bawitius bartheli. Mawsonia M. lybica Considered a "signature taxon" of the formation. A giant freshwater coelacanth. Species assignation deemed provisional due to the lack of neotype. Neoceratodus N. africanus A lungfish related to the living Australian species.ObaichthysO. africanusAn obaichthyid lepisosteiform. Remains formerly attributed to "Stromerichthys". Palaeonotopterus P. greenwoodi Nomen conservandum of the two Plethodus species previously described. Paranogmius P. doederleini Two incomplete skulls and several vertebrae. All definitive specimens were destroyed in World War II, however Concavotectum from the Kem Kem Beds of Morocco may be a synonym. Plethodus P. libycusP. tibniensis Holotypes destroyed in World War II, but now believed to have been misidentified Palaeonotopterus greenwoodi. Retodus R. tuberculatus A lungfish species identified from remains previously assigned to Neoceratodus. Saurodon Identified by Stromer in 1936, but now rejected due to this genus appearing only in post-Cenomanian Europe and North America. Now listed as Ichthyodectidae incertae sedis. Stromerichthys S. aethiopicusSkull, jaw, and opercular bones. A fish initially identified as a bowfin relative, but now thought to be a chimera consisting of remains assignable to Bawitius, Obaichthys, and others.
Testudines Testudines of the Bahariya Formation Genus Species Abundance Notes Images Apertotemporalis A. baharijensisAn incomplete skull A small bothremydid pleurodiran turtle. Now classified as a nomen dubium indeterminate beyond Bothremydidae. cf. Araripemydidae Indeterminate cf. Bothremydidae Indeterminate cf. Chelonioidea Indeterminate
Squamates Squamates of the Bahariya Formation Genus Species Abundance Notes Images Simoliophis Abundant First known sea snake, with functional hind legs. Now believed to include elements from different species and at least one of a different, unnamed genus.
Plesiosaurs Plesiosaurs of the Bahariya Formation Genus Species Abundance Notes Images Leptocleidus L. capensisFragmentary skull bones, teeth, and vertebrae. Formerly assigned to Leptocleidus capensis, a species known from the UK and South Africa.Cruickshank, Arthur. (1997). A Lower Cretaceous pliosauroid from South Africa. Annals of the South African Museum. (Annale van Die Suid-Afrikaanse Museum), 105, 207--226. Now considered an indeterminate polycotylid.
Crocodyliformes Crocodyliformes of the Bahariya Formation Genus Species Abundance Notes Images Aegyptosuchus A. peyeriAn incomplete skull. A poorly known, possibly stomatosuchid crocodile.HamadasuchusH. rebouli A terrestrial, dog-like peirosaurid. It is possible that some material previously attributed to Libycosuchus actually belongs to this species. Libycosuchus L. brevirostris A terrestrial crocodile of uncertain affinities, possibly related to Notosuchus. Stomatosuchus S. inermis A partial skull and two vertebrae. A large, flat-headed stomatosuchid with multiple small conical teeth, and possibly a pelican-like throat pouch. The only remains were destroyed in World War II. Stromerosuchus S. aegyptiacus Fragmentary remains Nomen dubium assigned to material found in 1911, that were badly damaged in 1922 while being shipped to Germany for study. Some material may belong to Aegyptosuchus and other to Stomatosuchus.
Pterosaurs Pterosaurs of the Bahariya Formation Genus Species Material Notes Images Ornithocheiriformes indet. Indeterminate Left first wing phalanx A medium-sized pterosaur. The first record of a pterosaur from Egypt.
Dinosaurs Sauropods Sauropods of the Bahariya Formation Genus Species Material Notes ImagesAegyptosaurusA. baharijensisThree caudal vertebrae, a scapula, and several limb bones."Table 13.1," in Weishampel, et al. (2004). Page 267.A small/medium sized titanosaurid. Due to the remains being destroyed and fragmentary, little is known about the taxon.Stromer, E. (1932a). Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltierreste der Baharîje-Stufe (unterstes Cenoman). 11. Sauropoda. Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematisch-naturwissenschaftliche Abteilung, Neue Folge, 10: 1-21.DicraeosaurusD. sp.An isolated caudal vertebra.Identified as Dicraeosaurus by Stromer in 1932. Subsequently considered a rebbachisaurid, or a third, unnamed titanosaur. Paralititan P. stromeri Four vertebrae, a scapula, and incomplete forelimb. An incomplete dorsal vertebra destroyed during WWII may also belong to P. stromeri. A large titanosaurid.Rebbachisauridae? indet.UnnamedAn isolated scapula.
Theropods Theropods of the Bahariya Formation Genus Species Abundance Notes ImagesAbelisauridae indet.UnnamedMUVP 477, an isolated caudal (tenth) cervical vertebra.A medium-sized abelisaurid, estimated around long.Abelisauridae? indet.UndescribedSeveral shed teeth crowns.A small-sized theropod, possibly an abelisaurid. Additionally, its teeth superficially resemble those of dromaeosaurids but likely come from a different kind of theropod. Bahariasaurus B. ingensA holotype specimen consisting of an incomplete postcranial skeleton. Several other specimens have been assigned including femora, vertebrae, and scapulae. A large-sized theropod known from several fragmentary skeletons, all of which are now lost. The affinities of this genus are unknown, though it may be a megaraptoran, ornithomimosaur, ceratosaur, or other form of theropod. Deltadromeus may be a synonym of Bahariasaurus, though this is unclear.CarcharodontosaurusC. saharicusA partial skull, teeth, and fragmentary postcranial remains.Reassigned to own genus and species, Tameryraptor.Ceratosauria?DeltadromeusD. agilisSeveral limb, pelvic, and pectoral girdle bones.Several remains originally referred to Bahariasaurus were referred to Deltadromeus. It is uncertain whether it and Bahariasaurus are synonymous or distinct. cf. Elaphrosauruscf. E. bambergi Two tibiae and a femur. Identified as cf. E. bambergi by Stromer in 1934. Now regarded as coming from a tetanuran, possibly a coelurosaur,Rauhut, O.W.M., and Carrano, M.T. (2016). The theropod dinosaur Elaphrosaurus bambergi Janensch, 1920, from the Late Jurassic of Tendaguru, Tanzania. Zoological Journal of the Linnean Society, (advance online publication) or "probable ceratosaur".aff. Erectopusaff. E. sauvageiAn incomplete right tibia.May have affinities with Ceratosauria or belong to Bahariasaurus or Deltadromeus. Spinosaurus "Spinosaurus B"One individual known from a fragmentary postcranial skeleton. Considered a distinct species of Spinosaurus by Ernst Stromer. It may instead belong to S. aegyptiacus, Sigilmassasaurus brevicollis, or its own species. Spinosaurus S. aegyptiacus One associated skeleton consisting of skull and postcranial bones. Fragmentary vertebrae, teeth, and other elements have also been found. A large spinosaurid. Tameryraptor T. markgrafiA partial skull, teeth, and fragmentary postcranial remains. A large carcharodontosaurid theropod, originally assigned to Carcharodontosaurus.
Flora