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Tridactyl theropod and ornithischian dinosaur tracks and trackways from Imilchil and Isli formations (Middle–?Late Jurassic, Bajocian–?) of the central High Atlas region (Morocco) are described. The Imilchil Formationconsists of brackish marine-continental deposits, and the Isli Formation is a continental red-bed succession. Considering numerous new footprint discoveries, including recently described Polyonyx sauropod trackways, tridactyl dinosaur tracks from the Imilchil-Tounfite region are revised. Dominating are theropod footprints resembling the ichnogenus Changpeipus and known from Lower-Middle Jurassic deposits of China. Other theropod ichnotaxa are Trisauropodiscus isp., cf. Wildeichnus isp.,Carmelopodus isp., Megalosauripus isp., Kayentapus isp. and an indeterminate small grallatorid. Ornithischians are represented by small indeterminate ornithischian tracks, large ornithischian footprints cf. Stegopodus isp. and a large indeterminate ornithopod form. Makers of the small theropod trackswere small coelurosaurs or basal tetanurans, larger forms belong toceratosaurs, megalosauroids, allosauroids or tyrannosauroids. Ornithischian tracks suggest dryomorphs, iguanodontians and thyreophorans as producers. Together with crocodylomorph and pterosaur tracks, invertebrate traces and plants, the Imilchil and Isli formations document a flourishing ecosystem and dinosaur habitat. Remarkable is the presence of Changpeipus theropod tracks known from abundant occurrences in East Asia. This suggests an exchange of dinosaur faunas between this region and northern Africa during the Middle Jurassic. [ABSTRACT FROM AUTHOR]

The Middle Jurassic-Lower Cretaceous continental "Red Beds" of the Moroccan Atlas have provided very interesting new taxa of charophytes and lacustrine ostracods: Aclistochara africana n.sp. (Bathonian), Feistiella atlantis n.sp. (Hauterivian-Lower Barremian), Cypridea suprajurassica n.sp., Cypridea mohandi n.sp. and Cypridea demnatensis n.sp. (Oxfordian ? - Kimmeridgian), Harbinia atlasica n.sp. (Hauterivian ? - Lower Barremian). Micropaleontological data obtained after 2002 contributed the following: * In the central High-Atlas, discovery of Upper Jurassic charophytes and freshwater ostracods (Dictyoclavator ramalhoi, Porochara kimmeridgensis, Aclistochara bransoni, Cypridea suprajurassica, Cypridea mohandi, Cypridea demnatensis) evince a Barremian ingression, its restricted marine character attested by lagoonal-brackish water ostracods (Harbinia atlasica) and presumed marine ostracods Trachyleberididae (cf. Strigosocythere strigosa, Cythereis ? sp., Protocythere ? sp.) associated with well-developed gypsiferous evaporites. * In the eastern High-Atlas, charophytes have been found at levels related to the Jurassic/Cretaceous boundary (Upper Tithonian–Berriasian Porochara maxima). * In the non-marine Lower Cretaceous (Hauterivian ? - Barremian) of the central High-Atlas, mixed Eurasian e and Gondwanian g assemblages of charophytes: Globator (e) and Feistiella (g), and brackish-lacustrine ostracods: (Fabanella-Cetacella (e), Darwinula-Cypridea-Harbinia (e & g) and Salvadoriella-Petrobrasia-Reconcavona-Paracypridea (g), were discovered. * Complementary data for the Lower Cretaceous charophyte biozonation (Upper Valanginian-Lower Barremian interval) with Globator hemiglobatoroides Mojon n.sp. (Cenozone M7a, NE-Spain) and Globator mutabilis (Cenozone M7b) from NE-Spain and Morocco (central High-Atlas) were obtained. * In the Moroccan Atlas area several stages in the breaking up of Pangea and the opening of the Atlantic Ocean have been recognized. These dislocations took place mainly during Bathonian times but also involved portions of the Kimmeridgian and Barremian.

In the eastern High Atlas (Morocco), continental "Red Beds" overlying the last marine deposits of Jurassic age consist of three main lithostratigraphic units: the Anoual Formation, the Ksar Metlili Formation and the Dekkar Group, bounded by two sharp sedimentary discontinuities. The Anoual Formation is a fluvial dominated deltaic plain deposit. It is followed by a final marine transgression of Early Bathonian age. The Ksar Metlili Formation found only in some subsident areas represents a renewal of fluvio-deltaic environments with a flora of Late Tithonian-Early Berriasian charophytes. The Dekkar Group occupies a larger area of sedimentation, its limits overlap the whole domain. From bottom to top, the succession indicates the existence of three paleoenvironments: alluvial fans deposits locally associated with Barremian?-Aptian lacustrine sediments containing charophytes and ostracods, alluvial plains deposits and finally, marine coastal to brackish plains deposits of the Cenomanian.After the closure of the Jurassic Atlasic marine trough, the eastern Atlasic "Red Beds" were deposited in response to three main geodynamic events: * the filling of the Atlasic trough with very thick deposits in subsiding areas linked to tectonic rifting during the Early Bathonian; * the emergence of this area caused a hiatus in sedimentation involving strata ranging in age from Bathonian to Barremian?-Aptian. However, continental sediments are preserved in some onshore geomorphological depressions at the Jurassic/Cretaceous boundary; * the opening of new basins, continental during the Barremian?-Aptian, that became marine during the Late Cenomanian as the result of Cenomanian-Turonian transgression. A comparison of the succession of events recorded in different parts of the Atlasic belts allows reconstruction of the three phases of paleogeographic evolution in these southern Tethyan areas during Middle Jurassic to Late Cretaceous times.

We describe an isolated small stegosaur pes track from the ?Upper Jurassic-?Lower Cretaceous red beds of the folded Middle Atlas, Morocco. It comes from the base of the Oued El Atchane Formation which unconformably overlies the Middle Jurassic (Upper Bathonian-? Callovian) El Mers III Formation. The footprint is preserved as concave epirelief together with a natural cast on a fluvial sandstone slab and is assigned here tentatively to cf. Stegopodus isp. The new discovery confirms the presence of this ichnogenus on the African continent and highlights similarities between the Jurassic-Cretaceous dinosaur faunas of North Africa and those of Asia, North America and Western Europe. [ABSTRACT FROM AUTHOR]

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In the Moroccan Central High Atlas, between the Bathonian and the Aptian, marine deposits are present in three continental formations. Known to be unfossiliferous for the main part, they are attributed to the Middle Jurassic or to the Lower Cretaceous, depending on the authors. Charophytes from the top of the second formation (Iouaridene Fm), and from the base of the third one (Jbel Sidal Formation), give an Upper Hauterivian–Lower Barremian age. Thanks to these biostratigraphical data, it has been possible to distinguish the different phases of the magmatic activity and the synsedimentary tectonic events, either linked to the closure of Tethyan Atlasic troughs during the Bathonian or associated with the development of the new basins, diachronous in the Atlasic Belt, during the Lower Cretaceous. [Copyright &y& Elsevier]