We report the discovery in Mesozoic continental “red beds” of Anoual Syncline, Morocco, of the new Guelb el Ahmar (GEA) fossiliferous sites in the Bathonian Anoual Formation. They produced one of the ...richest continental biotic assemblages from the Jurassic of Gondwana, including plants, invertebrates and vertebrates. Both the sedimentological facies and the biotic assemblage indicate a lacustrine depositional environment. The flora is represented by tree trunks (three families), pollen (13 species, five major clades) and charophytes. It suggests local forests and humid (non-arid) conditions. The vertebrate fauna is dominated by microvertebrates recovered by screening–washing. It is rich and diverse, with at least 29 species of all major groups (osteichthyans, lissamphibians, chelonians, diapsids, mammals), except chondrichthyans. It includes the first mammals discovered in the Middle Jurassic of Arabo-Africa. The GEA sites yielded some of the earliest known representatives of osteoglossiform fishes, albanerpetontid and caudate amphibians, squamates (scincomorphans, anguimorphan), cladotherian mammals, and likely choristoderes. The choristoderes, if confirmed, are the first found in Gondwana, the albanerpetontid and caudatan amphibians are among the very few known in Gondwana, and the anguimorph lizard is the first known from the Mesozoic of Gondwana. Mammals (Amphitheriida, cf. Dryolestida) remain poorly known, but are the earliest cladotherians known in Gondwana. The GEA biotic assemblage is characterized by the presence of Pangean and Laurasian (especially European) taxa, and quasi absence of Gondwanan taxa. The paleobiogeographical analysis suggests either a major fossil bias in Gondwana during the Middle Jurassic, and an overall vicariant Pangean context for the GEA assemblage, or alternatively, noticeable Laurasian (European) affinities and North-South dispersals. The close resemblance between the Bathonian faunas of GEA and Britain is remarkable, even in a Pangean context. The similarity between the local Anoual Syncline Guelb el Ahmar and Ksar Metlili faunas raises questions on the ?Berriasian age of the latter.
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•First discovered Middle Jurassic flora and fauna with microvertebrates from Africa•It yields the first Middle Jurassic mammals from Africa (stem Cladotheria).•The fauna has either Laurasian or Pangean affinities.
The genus
Macaca
belongs to Cercopithecidae (Old World monkeys), Cercopithecinae, Papionini. The presence of
Macaca
in North Africa is well known from the Late Miocene to the Late Pleistocene. ...However, the diet of fossil
Macaca
has been poorly described in the literature. In this study, we investigated the feeding habits of
Macaca
cf.
sylvanus
(
n
= 4) from the Plio-Pleistocene site Guefaït-4.2 in eastern Morocco through multiproxy analysis combining analyses of stable carbon and oxygen isotopes from tooth enamel, buccal microtexture, and low-magnification occlusal dental microwear. For both microwear analyses, we compared the macaques with a new reference collection of extant members of Cercopithecoidea. Our occlusal microwear results show for the fossil macaque a pattern similar to the extant
Cercocebus atys
and
Lophocebus albigena
, African forest-dwelling species that are characterized by a durophagous diet based mainly on hard fruit and seed intake. Buccal microtexture results also suggest the consumption of some grasses and the exploitation of more open habitats, similar to that observed in
Theropithecus gelada
. The δ
13
C of
M
. cf.
sylvanus
indicates a C
3
based-diet without the presence of C
4
plants typical of the savanna grassland in eastern Africa during this period. The high δ
18
O values of
M
. cf.
sylvanus
, compared with the contemporary ungulates recovered from Guefaït-4.2, could be associated with the consumption of a different resource by the primate such as leaves or fresh fruits from the upper part of trees. The complementarity of these methods allows for a dietary reconstruction covering a large part of the individual’s life.
Knowledge of continental faunas and floras from the Jurassic–Cretaceous transition in Gondwana, and especially in Africa, is limited. Here, we report the discovery of a rare assemblage of plants and ...aquatic reptiles from the Tithonian–Berriasian interval of the Anoual syncline in southeastern Morocco. Our preliminary field investigations led to the discovery of a disarticulated skeleton of a goniopholidid crocodylomorph, of a single fragment of a turtle plate, and of abundant plant remains, inviting further exploitation of the fossiliferous horizon. This assemblage indicates a freshwater habitat bordered by a lush moist conifer forest. Its taxonomic composition shows a strong similarity with better known contemporaneous Laurasian assemblages and stresses the paucity of coeval Gondwanan assemblages. Our discovery highlights that peri-Tethys continental assemblages may have shared common taxa and raises the question whether Laurasian and Gondwanan taxa from the Jurassic-Cretaceous transition were cosmopolitan, before they diverged later during the Cretaceous.
•We report on a new fossiliferous locality from the Tithonian-Berriasian interval of Morocco.•This continental assemblage preserves semi-aquatic reptiles and macro-floras.•This discovery represents a rare addition to the late Jurassic-early Cretaceous continental assemblages of Gondwana.•Perspectives on the evolution of continental ecosystems during the Jurassic-Cretaceous transition are presented.
Sedimentologic and lithostratigraphic studies carried out along the southern Front of the Central High Atlas in a mostly terrigenous Jurassic-Cretaceous series (Red beds) allow specifying the ...paleoenvironmental and paleogeographic evolution of three units: Guettioua, Ifezouane and Aoufous formations. The Bathonian Guettioua Fm, composed of terrigenous deposits of a median-distal piedmont and a proximal alluvial plain, is arranged into a regressive mesosequence. A terrigenous Lower (Mbr1) and an Upper (Mbr3) members of the Ifezouane Fm (Albian?-Cenomanian) were deposited in a median to a distal alluvial plain. Paleocurrent analysis indicates a southern source area of the terrigenous material mainly resulting from erosion of the neighbouring or distant Precambrian and Paleozoic basement. The southern origin of the material is opposite to a northern source proposed by authors for the surrounding western areas. These terrigenous supplies are interspersed with a lagoonal-marine incursion that covered the region during the deposition of a Middle Member (Mbr2) of the Ifezouane Fm. Fossiliferous limestone layers have yielded a restricted euryhaline microfauna and macrofauna. This restricted lagoon, E-W oriented with a multi-kilometre extension, was probably opened towards the East. By lateral correlations, this lagoonal-marine event can be dated to the Albian? - Cenomanian interval. This Cretaceous transgression, well documented for the first time, belongs to an earlier mesosequence recorder before the widespread and well-known Upper Cenomanian-Turonian transgression.
•Stratigraphic succession of Moroccan Jurassic-Cretaceous Reds beds.•Facies analysis, paleoenvironmental and palaeogeographic interpretations.•A first Albian?-Cenomanian lagoonal transgression detailed for the first time.•All detrital material come from the Saharan domain erosion.
Sedimentological and stratigraphical studies in the Cretaceous series of the Tendrara dome led to the discovery of fossiliferous levels in the pre-Cenomanian and Cenomanian deposits, providing ...significant biostratigraphic, paleoenvironmental, and paleogeographic results. In the SW part of the Tendrara dome, the predominantly terrigenous deposits at the base of the pre-Cenomanian (Dekkar 1 Formation) yielded dinosaur eggshell fragments and charophytes, in particular Clavatoraceans, pointing to the Barremian-Aptian. Above this unit, two beds with fish remains were discovered in the Dekkar 2 Formation and at the base of the Dekkar 3 Formation, respectively. To the NE of the Tendrara dome, a fossiliferous site with diversified benthic fauna and abundant fish remains was discovered in a thin marly unit unconformably overlying the Middle Jurassic basement. Elasmobranch micro-remains indicate a Cenomanian age for this unit. The SW-NE correlations indicate a marked thickness reduction and lateral facies variations, implying a strong asymmetry in the Cretaceous paleogeography of the dome. The first continental and lagoonal basins of the Barremian-Aptian and Albian?-Cenomanian are located in the southern part of the Tendrara dome. The Cenomanian transgression, initiated from the south, gradually covered the dome, depositing reduced coastal plain elasmobranch-rich facies in its northern part. The Tendrara dome constituted a paleogeographic barrier, limiting the first transgressions of the Cenomanian sea. This paleostructure is part of an emerged area (Idrissides High) located between the Tethyan Ocean and the Saharan epicontinental sea.
•Clavatoracean charophytes allow to date the Barremian-Aptian.•Elasmobranch associations indicate a Cenomanian age.•Lagoonal-marine precursor episodes of the Cenomanian-Turonian transgression.•Strongly differentiated pre-Cenomanian and Cenomanian paleogeography.•The Tendrara dome constituted a Cenomanian paleogeographic coastal edge.
The Ksar Metlili Formation, from the Jurassic – Cretaceous transition (Tithonian – Berriasian) of eastern High Atlas Mountains, Morocco, has yielded one of the richest microvertebrate assemblages ...from the Mesozoic of Gondwana. With at least 19 species, mammaliaforms are particularly diverse. ‘Dryolestoidea’ are the most abundant and the most diverse; nevertheless, only one species,
Donodon perscriptoris
Sigogneau-Russell,
1991a
, of the monotypic Donodontidae, had been described so far. Here, we describe four new species and three new genera of ‘dryolestoids’ from the Ksar Metlili deposits:
Donodon minor
sp. nov.,
Stylodens amerrukensis
gen. et sp. nov.,
Anoualestes incidens
gen. et sp. nov., and
Amazighodon orbis
gen. et sp. nov, all of which are included in the Donodontidae based on their dental morphology. We present the first phylogenetic analysis that incorporates the five donodontid species from the Ksar Metlili site into the cladotherian phylogeny. Our new analysis provides evidence for the paraphyly of the ‘Dryolestoidea’: Dryolestidae, ‘Paurodontidae’, Donodontidae, and Zatheria form a clade to the exclusion of the South American Meridiolestida. Donodontids are found to be closer to prototribosphenidans and zatherians than to any other ‘dryolestoid’ family and are more derived than meridiolestidans. This topology refutes a previous hypothesis that meridiolestidans are phylogenetically rooted among donodontids. Our phylogenetic analysis also supports Donodontidae as an endemic African monophyletic group. The close relationships of the donodontids and zatherians suggest that zatherians had a geographical origin possibly from Africa or Gondwana instead of Laurasia.
We describe small-sized specimens of the metailurine felid Dinofelis from a new Plio-Pleistocene site in North Africa. Dinofelis is a genus of saber-toothed cats mainly recorded from East and South ...Africa with numerous leopard to jaguar-sized species. The described specimens, clearly smaller than all the other African Dinofelis, resemble isolated remains from the Late Pliocene of France and the Early Pleistocene of Africa. Present evidence suggests that our form represents a new species and/or new lineage of Dinofelis, smaller and probably occupying a different ecological niche compared to the previously known members of the genus, and thus it adds complexity to the high intraspecific competition among large carnivorans in the Plio-Pleistocene of Africa.
•We describe small-sized specimens of the felid Dinofelis from a new Plio-Pleistocene site in North Africa.•The described specimens, clearly smaller than all the other African Dinofelis.•Present evidence suggests that our form represents a new lineage of Dinofelis, smaller and probably occupying a different ecological niche.
The northern boundary of the Central High Atlas was affected by a transgression during the Aptian that reached the junction zone between the Middle and the High Atlas. In this sector (Naour-Aghbala) ...which corresponds to the presumed closure zone of this Aptian Atlantic marine trough, the sedimentary record reveals a strong dependence on the regional structural framework. The Barremian continental sedimentation is concentrated in an elongated W-E highly subsiding zone, limited to the south by the polyphase Aghbala-Afourer Fault Zone (AAFZ), which corresponds to the contact between the main Atlasic Belt and its northern boundary (Beni Mellal Atlas). The Aptian deposits preserve similar littoral marine characters from West to East without showing any confined facies, which could evoke the eastern limit of the gulf. On the other hand, towards the North, the Aptian layers rapidly change from marine to lagoonal then to continental facies. The paleogeographic boundary of the Aptian shoreline, oriented E-W, is locally controlled by the North El Ksiba Fault (NKF) in the North. The Aptian Atlantic transgression, closely linked to the narrow Barremian graben, shows a wide northward extension of the marine sedimentary area.
The Barremian graben highlighted in the Aghbala-Naour area represents only a segment of a major east-west intracontinental rift that continued eastward with the more recent frontal thrust of the eastern Moroccan High Atlas. This faulted structure was the penetration axis of a double transgression: from the Tethys to the East and from the Atlantic Ocean to the West on the emerged Atlasic domain.
•Identification of an E-W intracontinental Barremian graben in the Aghbala-Naour area.•Evidence of an Aptian paleogeographic S–N zoning from marine to continental deposits.•Geodynamic evolution from Barremian intracontinental rift to Aptian marine gulf.•Extensional faulting between Atlantic & Tethyan Oceans, across the High Atlas domain.
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