Anoual Formation

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Anoual Formation
Stratigraphic range: Early Bathonian
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Type Geological formation
Unit of Anoual Syncline
Sub-unitsLower Member, Upper Member
Underlies Unconformity with Ksar Metlili Formation
Overlies Pholadomya Marls and Limestones Formation
Thickness~500 m (1,600 ft)
Lithology
Primary Mudstone (Lower), limestone (Upper)
Other Sandstone, limestone, marl (Lower)
Location
Coordinates 32°30′N3°06′W / 32.5°N 3.1°W / 32.5; -3.1
Approximate paleocoordinates 26°54′N0°54′E / 26.9°N 0.9°E / 26.9; 0.9
Region Figuig Province
CountryFlag of Morocco.svg  Morocco
Extent High Atlas
Type section
Named for Anoual
Morocco relief location map.jpg
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Anoual Formation (Morocco)

The Anoual Formation is a geological formation in the High Atlas of Morocco. It is early Bathonian in age. It consists of two members. The lower member is several hundred metres thick, and consists largely of mudstone with lens beds of cross bedded sandstone, with thin intercalations of limestone that was deposited in a continental setting. The upper member is several tens of metres thick and consists of limestone deposited in a shallow marine setting. The formation is fossiliferous, with several of the limestone intercalations yielding a diverse fauna, including amphibians, reptiles, dinosaurs and mammals. [1]

Contents

Paleobiota

Fish

Fish
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Arganodus IndeterminateIsolated tooth plates Lungfish
Lepidotes / Scheenstia IndeterminateIsolated teeth and scales
cf. Ionoscopiformes IndeterminateRhomboidal scales
Mawsoniidae IndeterminateSkull bones including a parasphenoid Coelacanth
Osteoglossiformes IndeterminateSquamules (small scales)

Amphibians

Amphibians
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Albanerpetontidae IndeterminateIncomplete premaxilla and incomplete frontal
? Caudata IndeterminateFragment of a dentary
? Lissamphibia IndeterminateFragment of a maxilla

Turtles

Turtles
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Testudinata IndeterminateShell fragmentsProbably 4 distinct taxa

Lepidosaurs

Lepidosaurs
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
cf. Parviraptor IndeterminateFour vertebral centra
Rhynchocephalia IndeterminateOne fragment of dentary bearing two incomplete teeth, one fragment of maxilla bearing the bases of two teeth.
Scincomorpha IndeterminateA fragment of bone bearing teeth, potentially a fragment of bone bearing one complete tooth
Squamata IndeterminateIncomplete maxilla, incomplete dorsal vertebra, one proximal part of femur

Choristoderes

Choristoderes
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Choristodera IndeterminateFragmentary dentary, centrum of an anterior caudal vertebra, possibly centrum of a dorsal vertebraSimilar to Cteniogenys

Dinosaurs

Dinosaurs
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Theropoda IndeterminateSeveral teeth
Ornithischia IndeterminateToothSimilar to Alocodon
cf. Stegosauria IndeterminatePoorly preserved tooth

Pterosaurs

Pterosaurs
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Rhamphorhynchidae IndeterminateTeeth
Pterosauria IndeterminateTeethSimilar to wukongopterids

Crocodyliformes

Crocodyliformes
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
cf. Theriosuchus IndeterminateTeeth
Atoposauridae IndeterminateTeeth
Teleosauridae IndeterminateTeeth
Thalattosuchia IndeterminateTeeth, various skeletal elements probably belonging to a single individual

Mammals

Mammals
GenusSpeciesLocationStratigraphic positionAbundanceNotesImages
Amphitheriidae IndeterminateFragment of right dentary of a juvenile individual with an anterior lower premolar and a replacing posterior premolar, fragment of an edentulous right dentary, probably middle-posterior part.Both fragments probably belong to the same taxon
Dryolestida IndeterminateFragment of a tooth bearing one cusp and one root

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References

  1. Haddoumi, Hamid; Allain, Ronan; Meslouh, Said; Metais, Grégoire; Monbaron, Michel; Pons, Denise; Rage, Jean-Claude; Vullo, Romain; Zouhri, Samir (January 2016). "Guelb el Ahmar (Bathonian, Anoual Syncline, eastern Morocco): First continental flora and fauna including mammals from the Middle Jurassic of Africa" (PDF). Gondwana Research. 29 (1): 290–319. Bibcode:2016GondR..29..290H. doi:10.1016/j.gr.2014.12.004. ISSN   1342-937X.