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Silty noduliferous shales in the lower part of the Middle Ordovician (late Darriwilian 2) Taddrist Formation in the central Moroccan Anti-Atlas contain a unique assemblage of conulariids consisting of one species each of Archaeoconularia Bouček, 1939, Glyptoconularia Sinclair, 1952, and Pseudoconularia Bouček, 1939. Glyptoconularia antiatlasica new species, currently represented by a single three-dimensional specimen, is the first member of this extremely rare, highly autapomorphic genus to be described from outside of cratonic North America as well as the first Glyptoconularia from the Middle Ordovician. Pseudoconularia cf. P. grandissima (Barrande, 1867) and Archaeoconularia cf. A. exquisita (Barrande, 1867) most closely resemble species previously described from Middle and Upper Ordovician strata in the Prague Basin (Czech Republic), then located adjacent to North Africa. Anaconularia anomala (Barrande, 1867), previously known from the Upper Ordovician (Sandbian) Libeň and Letná formations in the Prague Basin, is documented for the first time from the Upper Ordovician (Katian) Upper Tioririne Formation of Morocco. In addition to extending the known stratigraphical and paleogeographical ranges of these conulariids, results of the present investigation add to the list of invertebrate taxa that appear to have originated during Early or Mid-Ordovician times in peri-Gondwana or south-polar Gondwana, and then migrated to the eastern margin of Laurentia, arriving there along with other cool-water taxa during the Sandbian-Katian transition. UUID: http://zoobank.org/9ea5051b-cff5-4911-861a-531db4f45883 [ABSTRACT FROM AUTHOR]

Two species of cornulitids, Cornulites gondwanensis sp. nov. and C. aff. shallochensis Reed are described from the Hirnantian of Morocco, within an assemblage representative of the Hirnantia brachiopod fauna occurring near the Ordovician South Pole. The dominance of aggregated and solitary free forms could be explained by particular sedimentary environments preceding the Hirnantian glaciation and the latest Ordovician Extinction Event. The diversity of cornulitids in the Late Ordovician of Gondwana and related terranes was relatively low, and less diverse than the cornulitids of Laurentia and Baltica. Hirnantian cornulitids from Morocco do not resemble Late Ordovician cornulitids of Baltica and Laurentia. Moroccan cornulitids seem to be closely allied to some older Gondwanan cornulitids, especially Sardinian ones. They resemble species described from the Late Ordovician and Llandovery of Scotland suggesting a palaeobiogeographic link. [ABSTRACT FROM AUTHOR]

This study documents conodont faunas of the Fezouata Formation, recovered from the AZ-1 borehole at Adrar Zouggar Mountain and from outcrops near Zagora in south-eastern Morocco. The Fezouata Formation was deposited on the peri-Gondwanan shelf near the South Pole during Early Ordovician times. It is composed of mostly fine-grained siliciclastics and is well known for including beds displaying the exceptionally well preserved Fezouata Biota. Studies on different microfossil groups, including conodonts, increase the diversity recorded from this exceptional ecosystem. Strongly recrystallised conodont elements were extracted from the fine-grained siliciclastic sediments by diluted hydrofluoric acid (HF), which was used for isolating palynomorphs. The material is dominated by simple cone taxa such as Parapaltodus , Semiacontiodus , Scolopodus , Scalpellodus , Drepanoistodus , Acodus , Paltodus , and Cornuodus . In addition, a few elements of early Prioniodus are recovered. This composition allows an estimation of uppermost Tremadocian through basal Floian ages for the fragmented elements because characteristic elements of younger assemblages, including ramiform (e.g., Oepikodus , Baltoniodus ) or coniform (e.g., Tropodus , Protopanderodus ) apparatuses, have not been recorded. The association is devoid of any warm/tropical and temperate water taxa and is typical for faunas in the cold water environments of the subpolar siliciclastic shelves during Early Ordovician times. The new term of ‘subpolar faunal domain’ is proposed for these conodont associations of low diversity that occur at high southern latitudes during the Early Ordovician. Ecological implications and palaeobiogeographical relationships of the conodont faunas are discussed. [ABSTRACT FROM AUTHOR]