Anoual Formation

Anoual Formation
Stratigraphic range: Early Bathonian
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TypeGeological formation
Unit ofAnoual Syncline
Sub-unitsLower Member, Upper Member
UnderliesUnconformity with Ksar Metlili Formation
OverliesPholadomya Marls and Limestones Formation
Thickness~500 m (1,600 ft)
Lithology
PrimaryMudstone (Lower), limestone (Upper)
OtherSandstone, limestone, marl (Lower)
Location
Coordinates32°30′N 3°06′W / 32.5°N 3.1°W / 32.5; -3.1
Approximate paleocoordinates26°54′N 0°54′E / 26.9°N 0.9°E / 26.9; 0.9
RegionFiguig Province
Country Morocco
ExtentHigh Atlas
Type section
Named forAnoual
Anoual Formation is located in Morocco
Anoual Formation
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 freshwater continental setting, likely lacustrine or palustrine, with small marine influences.[1] 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.[2]

Paleobiota

Brachiopoda

Genus Species Location Stratigraphic Position Material Notes Images
Burmirhynchia[3]
  • B. gr. termierae-athiaensis
 Anoual Upper Member Isolated shells A Branchiopod of the family Tetrarhynchiidae
Kallirhynchia[3]
  • K. oranensis
 Anoual Upper Member Isolated shells A Branchiopod of the family Tetrarhynchiidae
Kallirhynchia specimen

Crustacea

Genus Species Location Stratigraphic Position Material Notes Images
Asciocythere[3]
  • A. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the family Schulerideidae.
Bythocypris[3]
  • B. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the family Bythocyprididae
Asciocythere[3]
  • A. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the family Schulerideidae.
Cypridea[3]
  • C. cf. postelongata
 Anoual Lower Member Isolated Valves A Freshwater Ostracod of the family Cyprididae
Cypris[3]
  • C. spp.
 Anoual Lower Member Isolated Valves A Freshwater Ostracod of the family Cyprididae
Darwinula[3]
  • D. magna
  • D. cf. leguminella
 Anoual Lower Member Isolated Valves A Freshwater Ostracod of the family Darwinulidae
Fabanella[3]
  • F. bathonica
  • F. sp.
 Anoual Upper Member Isolated Valves A Freshwater Ostracod of the order Podocopida
Fastigocythere[3]
  • F. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the order Podocopida
Klieana[1]
  • K. levis
 Anoual Upper Member Isolated Valves A Freshwater Ostracod of the order Cytherideidae
Kinkelinella[1]
  • K. sp.
 Anoual Lower Member Isolated Valves A Freshwater/Brackish Ostracod of the family Protocytheridae
Mantelliana[1]
  • M. sp.
 Anoual Lower Member Isolated Valves A Freshwater Ostracod of the family Cyprididae
Metacypris[3]
  • M. sp.
 Anoual Lower Member Isolated Valves A Freshwater/Brackish Ostracod of the family Limnocytheridae
Paracypris[3]
  • P. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the family Candonidae. Dominant marine taxon
Pneumatocythere[3]
  • P.? juglandiformis
 Anoual Upper Member Isolated Valves A Marine Ostracod of the order Podocopida
Praeschuleridea[3]
  • P. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the family Candonidae.
Procytheridea[1]
  • P. sp.
 Anoual Upper Member Isolated Valves A Marine Ostracod of the order Podocopida
Scabriculocypris[1]
  • S. sp.
 Anoual Lower Member Isolated Valves A Freshwater Ostracod of the family Cyprididae
Theriosynoecum[1]
  • T. sp.
 Anoual Lower Member Isolated Valves A Freshwater/Brackish Ostracod of the family Limnocytheridae

Mollusca

Genus Species Location Stratigraphic Position Material Notes Images
Lymnaeidae[2] Indeterminate Guelb el Ahmar Lower Member Isolated shells Freshwater snails
Nerineidae[1] Indeterminate Anoual Upper Member Isolated shells Marine snails
Planorbidae[2] Indeterminate Guelb el Ahmar Lower Member Isolated shells Freshwater snails
Provalvata[1] P. sp. Anoual Lower Member Isolated shells Freshwater snail of the family Provalvatidae
Valvatidae[2] Indeterminate Guelb el Ahmar Lower Member Isolated shells Freshwater snails

Fish

Abundant osteichthyan ichthyoliths are know. An isolated spine displaying characters seen in extant cypriniform or siluriform fishes has been recovered, alternatively can belong to a member of Myriacanthidae.[2]

Genus Species Location Stratigraphic Position Material Notes Images
Arganodus[2] Indeterminate Guelb el Ahmar Lower Member Isolated tooth plates Lungfish
Arganodus reconstruction
Lepidotes/Scheenstia[2] Indeterminate Guelb el Ahmar Lower Member Isolated teeth and scales Lepidotidae bony fish
Lepidotes reconstruction
cf. Ionoscopiformes[2] Indeterminate Guelb el Ahmar Lower Member Rhomboidal scales Tentatively assigned to Ophiopsidae
Mawsoniidae[2] Indeterminate Guelb el Ahmar Lower Member Skull bones including a parasphenoid Coelacanth
Osteoglossiformes[2] Indeterminate Guelb el Ahmar Lower Member Squamules (small scales) The oldest record of the group

Amphibians

Genus Species Location Stratigraphic Position Material Notes Images
Albanerpetontidae[2] Indeterminate Guelb el Ahmar Lower Member Incomplete premaxilla and incomplete frontal Likely represents a new taxon
Caudata?[2] Indeterminate Guelb el Ahmar Lower Member Fragment of a dentary
Lissamphibia?[2] Indeterminate Guelb el Ahmar Lower Member Fragment of a maxilla

Turtles

Genus Species Location Stratigraphic Position Material Notes Images
Araripemydidae?[2] Indeterminate Guelb el Ahmar Lower Member Shell Fragments Resembles both Araripemydids and Trionychidae
Cryptodira?[2] Indeterminate Guelb el Ahmar Lower Member Shell Fragments Resembles younger-aged Solemydidae and Pleurosternidae taxa
Testudinata[2] Indeterminate Guelb el Ahmar Lower Member Shell Fragments Neural plate slightly longer than wide
Testudinata[2] Indeterminate Guelb el Ahmar Lower Member Shell Fragments Represented by smooth plates

Lepidosaurs

Genus Species Location Stratigraphic Position Material Notes Images
cf.Parviraptor[2] Indeterminate Guelb el Ahmar Lower Member Four vertebral centra
Rhynchocephalia[2] Indeterminate Guelb el Ahmar Lower Member One fragment of dentary bearing two incomplete teeth, one fragment of maxilla bearing the bases of two teeth.
Scincomorpha[2] Indeterminate Guelb el Ahmar Lower Member A fragment of bone bearing teeth, potentially a fragment of bone bearing one complete tooth
Squamata[2] Indeterminate Guelb el Ahmar Lower Member Incomplete maxilla, incomplete dorsal vertebra, one proximal part of femur

Choristoderes

Genus Species Location Stratigraphic Position Material Notes Images
Choristodera[2] Indeterminate Guelb el Ahmar Lower Member Fragmentary dentary, centrum of an anterior caudal vertebra, possibly centrum of a dorsal vertebra Similar to Cteniogenys

Dinosaurs

Genus Species Location Stratigraphic Position Material Notes Images
Theropoda[2] Indeterminate Guelb el Ahmar Lower Member Several teeth
Ornithischia[2] Indeterminate Guelb el Ahmar Lower Member Tooth Similar to Alocodon
cf.Stegosauria[2] Indeterminate Guelb el Ahmar Lower Member Poorly preserved tooth

Pterosaurs

Genus Species Location Stratigraphic Position Material Notes Images
Rhamphorhynchidae[2] Indeterminate Guelb el Ahmar Lower Member Teeth
Pterosauria[2] Indeterminate Guelb el Ahmar Lower Member Teeth Similar to wukongopterids

Crocodyliformes

Genus Species Location Stratigraphic Position Material Notes Images
cf.Theriosuchus[2] Indeterminate Guelb el Ahmar Lower Member Teeth
Atoposauridae[2] Indeterminate Guelb el Ahmar Lower Member Teeth
Teleosauridae[2] Indeterminate Guelb el Ahmar Lower Member Teeth
Thalattosuchia[2] Indeterminate Guelb el Ahmar Lower Member Teeth, various skeletal elements probably belonging to a single individual

Mammals

Genus Species Location Stratigraphic Position Material Notes Images
Amphitheriidae[2] Indeterminate Guelb el Ahmar Lower Member Fragment 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[2] Indeterminate Guelb el Ahmar Lower Member Fragment of a tooth bearing one cusp and one root

Charophyta

Genus Species Location Stratigraphic Position Material Notes Images
Aclistochara[4] A. africana Guelb el Ahmar Lower Member Gyrogonites A Characean algae of the family Characeae
Porochara[3] P. hians Anoual Lower Member Oogonia A characean algae of the family Porocharaceae

Palynology

Genus Species Location Stratigraphic Position Material Notes Images
Alisporites[2]
  • A. spp.
 Guelb el Ahmar Lower Member Pollen Affinities with the families Peltaspermaceae or Corystospermaceae
Araucariacites[2]
  • A. australis
 Guelb el Ahmar Lower Member Spores Affinities with Araucariaceae in the Pinales.
Extant Araucaria.
Callialasporites[2]
  • C. spp.
 Guelb el Ahmar Lower Member Pollen Affinities with Araucariaceae inside Coniferae.
Classopollis[2]
  • C. spp.
 Guelb el Ahmar Lower Member Pollen Affinities with Cheirolepidiaceae inside Coniferae.
Cyathidites[2]
  • C. sp.
 Guelb el Ahmar Lower Member Spores Affinities with the family Cyatheaceae inside Cyatheales. Arboreal Fern Spores
Example of extant Cyathea, Cyathidites come probably from similar genera
Cycadopites[2]
  • C. spp.
 Guelb el Ahmar Lower Member Pollen Affinities with the Cycadopsida inside Cycadales. Pollen related with modern Cycas
Encephalartos, Cycadopites come probably from similar genera
Inaperturopollenites[2]
  • I. spp.
 Guelb el Ahmar Lower Member Pollen Affinities with the Pinidae inside Coniferae.
Extant Pinus Cone. Inaperturopollenites is similar to the pollen found on this genus
Ischyosporites[2]
  • I. cf. variegatus
  • I. sp
 Guelb el Ahmar Lower Member Spores Affinities with Pteridopsida, likely derived from a member of Anemiaceae
Extant Anemia specimens; Ischyosporites probably comes from similar genera
Leptolepidites[2]
  • L. spp.
 Guelb el Ahmar Lower Member Spores Affinities with the family Dennstaedtiaceae in the Polypodiales. Forest fern spores.
Extant Dennstaedtia specimens; Leptolepidites probably comes from similar genera
Pityosporites[2]
  • P. sp.
 Guelb el Ahmar Lower Member Pollen Affinities with the Pinidae inside Coniferae.

Fossil Wood

Genus Species Location Stratigraphic Position Material Notes Images
Agathoxylon[2]
  • A. aff. sahariense
  • Guelb el Ahmar
  • Oued Metlili
 Lower Member Fossil Wood Conifer fossil wood of the family Araucariaceae
Metapodocarpoxylon[2]
  • M. libanoticum
  • Guelb el Ahmar
  • Oued Metlili
 Lower Member Fossil Wood Conifer fossil wood of the family Podocarpaceae
Protopodocarpoxylon[2]
  • P. subrochii
  • P. teixeirae
  • Guelb el Ahmar
  • Oued Metlili
 Lower Member Fossil Wood Conifer fossil wood of the family Hirmeriellaceae
Phyllocladoxylon[2]
  • P. atlasicum
  • Guelb el Ahmar
  • Oued Metlili
 Lower Member Fossil Wood Conifer fossil wood of the family Podocarpaceae

References

  1. ^ a b c d e f g h i Haddoumi, Hamid; Charrière, André; Andreu, Bernard; Mojon, Pierre-Olivier (2008). "Les dépôts continentaux du Jurassique moyen au Crétacé inférieur dans le Haut Atlas oriental (Maroc) : paléoenvironnements successifs et signification paléogéographique". Carnets de Géologie / Notebooks on Geology. CG2008 (A06): 1–29.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au 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.
  3. ^ a b c d e f g h i j k l m n o Haddoumi, Hamid; Aiméras, Yves; Bodergat, Anne-Marie; Charrière, André; Mangold, Charles; Benshili, Khadija (1998-07-01). "Âges et environnements des Couches rouges d'Anoual (Jurassique moyen et Crétacé inférieur, Haut-Atlas oriental, Maroc)". Comptes Rendus de l'Académie des Sciences - Series IIA - Earth and Planetary Science. 327 (2): 127–133. doi:10.1016/S1251-8050(98)80043-8. ISSN 1251-8050.
  4. ^ MOJON, Pierre-Olivier; HADDOUMI, Hamid; CHARRIÈRE, André (2009). "Nouvelles données sur les Charophytes et Ostracodes du Jurassique moyen-supérieur - Crétacé inférieur de l'Atlas marocain". Carnets de géologie (Notebooks on geology) (Mémoires). doi:10.4267/2042/29781. ISSN 1634-0744.