Anoual Formation
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. 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.
Paleobiota
Brachiopoda
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Burmirhynchia |
|
Anoual | Upper Member | Isolated shells | A Branchiopod of the family Tetrarhynchiidae | |
Kallirhynchia |
|
Anoual | Upper Member | Isolated shells | A Branchiopod of the family Tetrarhynchiidae |
Crustacea
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Asciocythere |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the family Schulerideidae. | |
Bythocypris |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the family Bythocyprididae | |
Asciocythere |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the family Schulerideidae. | |
Cypridea |
|
Anoual | Lower Member | Isolated Valves | A Freshwater Ostracod of the family Cyprididae | |
Cypris |
|
Anoual | Lower Member | Isolated Valves | A Freshwater Ostracod of the family Cyprididae | |
Darwinula |
|
Anoual | Lower Member | Isolated Valves | A Freshwater Ostracod of the family Darwinulidae | |
Fabanella |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the order Podocopida | |
Fastigocythere |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the order Podocopida | |
Klieana |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the order Cytherideidae | |
Kinkelinella |
|
Anoual | Lower Member | Isolated Valves | A Freshwater/Brackish Ostracod of the family Protocytheridae | |
Mantelliana |
|
Anoual | Lower Member | Isolated Valves | A Freshwater Ostracod of the family Cyprididae | |
Metacypris |
|
Anoual | Lower Member | Isolated Valves | A Freshwater/Brackish Ostracod of the family Limnocytheridae | |
Paracypris |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the family Candonidae. Dominant marine taxon | |
Pneumatocythere |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the order Podocopida | |
Praeschuleridea |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the family Candonidae. | |
Procytheridea |
|
Anoual | Upper Member | Isolated Valves | A Marine Ostracod of the order Podocopida | |
Scabriculocypris |
|
Anoual | Lower Member | Isolated Valves | A Freshwater Ostracod of the family Cyprididae | |
Theriosynoecum |
|
Anoual | Lower Member | Isolated Valves | A Freshwater/Brackish Ostracod of the family Limnocytheridae |
Mollusca
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Lymnaeidae | Indeterminate | Guelb el Ahmar | Lower Member | Isolated shells | Freshwater snails | |
Nerineidae | Indeterminate | Anoual | Upper Member | Isolated shells | Marine snails | |
Planorbidae | Indeterminate | Guelb el Ahmar | Lower Member | Isolated shells | Freshwater snails | |
Provalvata | P. sp. | Anoual | Lower Member | Isolated shells | Freshwater snail of the family Provalvatidae | |
Valvatidae | 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.
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Arganodus | Indeterminate | Guelb el Ahmar | Lower Member | Isolated tooth plates | Lungfish | |
Lepidotes/Scheenstia | Indeterminate | Guelb el Ahmar | Lower Member | Isolated teeth and scales | Lepidotidae bony fish | |
cf. Ionoscopiformes | Indeterminate | Guelb el Ahmar | Lower Member | Rhomboidal scales | Tentatively assigned to Ophiopsidae | |
Mawsoniidae | Indeterminate | Guelb el Ahmar | Lower Member | Skull bones including a parasphenoid | Coelacanth | |
Osteoglossiformes | 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 | Indeterminate | Guelb el Ahmar | Lower Member | Incomplete premaxilla and incomplete frontal | Likely represents a new taxon | |
Caudata? | Indeterminate | Guelb el Ahmar | Lower Member | Fragment of a dentary | ||
Lissamphibia? | Indeterminate | Guelb el Ahmar | Lower Member | Fragment of a maxilla |
Turtles
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Araripemydidae? | Indeterminate | Guelb el Ahmar | Lower Member | Shell Fragments | Resembles both Araripemydids and Trionychidae | |
Cryptodira? | Indeterminate | Guelb el Ahmar | Lower Member | Shell Fragments | Resembles younger-aged Solemydidae and Pleurosternidae taxa | |
Testudinata | Indeterminate | Guelb el Ahmar | Lower Member | Shell Fragments | Neural plate slightly longer than wide | |
Testudinata | Indeterminate | Guelb el Ahmar | Lower Member | Shell Fragments | Represented by smooth plates |
Lepidosaurs
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
cf.Parviraptor | Indeterminate | Guelb el Ahmar | Lower Member | Four vertebral centra | ||
Rhynchocephalia | 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 | Indeterminate | Guelb el Ahmar | Lower Member | A fragment of bone bearing teeth, potentially a fragment of bone bearing one complete tooth | ||
Squamata | 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 | 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 | Indeterminate | Guelb el Ahmar | Lower Member | Several teeth | ||
Ornithischia | Indeterminate | Guelb el Ahmar | Lower Member | Tooth | Similar to Alocodon | |
cf.Stegosauria | Indeterminate | Guelb el Ahmar | Lower Member | Poorly preserved tooth |
Pterosaurs
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Rhamphorhynchidae | Indeterminate | Guelb el Ahmar | Lower Member | Teeth | ||
Pterosauria | Indeterminate | Guelb el Ahmar | Lower Member | Teeth | Similar to wukongopterids |
Crocodyliformes
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
cf.Theriosuchus | Indeterminate | Guelb el Ahmar | Lower Member | Teeth | ||
Atoposauridae | Indeterminate | Guelb el Ahmar | Lower Member | Teeth | ||
Teleosauridae | Indeterminate | Guelb el Ahmar | Lower Member | Teeth | ||
Thalattosuchia | 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 | 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 | 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 | A. africana | Guelb el Ahmar | Lower Member | Gyrogonites | A Characean algae of the family Characeae | |
Porochara | P. hians | Anoual | Lower Member | Oogonia | A characean algae of the family Porocharaceae |
Palynology
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Alisporites |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with the families Peltaspermaceae or Corystospermaceae | |
Araucariacites |
|
Guelb el Ahmar | Lower Member | Spores | Affinities with Araucariaceae in the Pinales. | |
Callialasporites |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with Araucariaceae inside Coniferae. | |
Classopollis |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with Cheirolepidiaceae inside Coniferae. | |
Cyathidites |
|
Guelb el Ahmar | Lower Member | Spores | Affinities with the family Cyatheaceae inside Cyatheales. Arboreal Fern Spores | |
Cycadopites |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with the Cycadopsida inside Cycadales. Pollen related with modern Cycas | |
Inaperturopollenites |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with the Pinidae inside Coniferae. | |
Ischyosporites |
|
Guelb el Ahmar | Lower Member | Spores | Affinities with Pteridopsida, likely derived from a member of Anemiaceae | |
Leptolepidites |
|
Guelb el Ahmar | Lower Member | Spores | Affinities with the family Dennstaedtiaceae in the Polypodiales. Forest fern spores. | |
Pityosporites |
|
Guelb el Ahmar | Lower Member | Pollen | Affinities with the Pinidae inside Coniferae. |
Fossil Wood
Genus | Species | Location | Stratigraphic Position | Material | Notes | Images |
---|---|---|---|---|---|---|
Agathoxylon |
|
|
Lower Member | Fossil Wood | Conifer fossil wood of the family Araucariaceae | |
Metapodocarpoxylon |
|
|
Lower Member | Fossil Wood | Conifer fossil wood of the family Podocarpaceae | |
Protopodocarpoxylon |
|
|
Lower Member | Fossil Wood | Conifer fossil wood of the family Hirmeriellaceae | |
Phyllocladoxylon |
|
|
Lower Member | Fossil Wood | Conifer fossil wood of the family Podocarpaceae |
References
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.