Nouvelles données sur Phosphatherium escuilliei (Mammalia, Proboscidea) de l'Éocène inférieur du Maroc, apports à la phylogénie des Proboscidea et des ongulés lophodontes 6208 Rabat-Instituts (Maroc)

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Early Tertiary pseudotoothed birds.

71 p. : ill., map ; 26 cm. "December 20, 2010."We describe here new specimens of pseudotoothed birds (Odontopterygiformes) from the Upper Paleocene and Lower Eocene of the Ouled Abdoun Basin, Morocco. These Lower Paleogene fossils are among the oldest representatives of the Odontopterygiformes and include braincases, beak fragments, and long bones. Dasornis toliapica (Owen, 1873) (2-3 m wingspan) and Dasornis emuinus (Bowerbank, 1854) (3.5-4.5 m wingspan) were initially described from the Lower Eocene London Clay of Sheppey, England. The new species Dasornis abdoun (1.5-1.7 m wingspan) constitutes the smallest species of pseudotoothed bird ever discovered. We partly revise the oversplit taxonomy of the odontopterygiforms: the two species from the Paleogene of England and Morocco are regarded as congeneric, the name Dasornis having priority over the name Odontopteryx. We also synonymize Neptuniavis minor Harrison and Walker, 1977, and Macrodontopteryx oweni Harrison and Walker, 1976, with D. toliapica (Owen, 1873). Moreover, the genera Pelagornis Lartet, 1857, and Osteodontornis Howard, 1957, are regarded as pertaining to one single taxonomic entity that corresponds to the Pelagornis morphotype. In Dasornis, the morphological peculiarities of the humerus that are related to gliding flight are less pronounced than in Pelagornis. The latter taxon includes exceedingly specialized gliders that were most likely unable of sustained flapping flight and relied almost entirely on winds to provide lift. Pseudotoothed birds pertaining to the Dasornis morphotype were more generalists and could probably undertake flapping flight, even if limited. The species of Dasornis were soaring pelagic feeders that could disperse over large territories like extant albatrosses. They formed large breeding colonies near the shore of the northeastern part of the Moroccan phosphate sea, some 55 million years ago. Our work provides evidence that Dasornis was widespread in the early Tertiary, as it is currently known from the Lower Paleogene deposits of Morocco, England, and Kazakhstan. Paleoenvironmental studies show that these marine deposits formed in a tropical climate. This could explain the occurrence of both Dasornis and prophaethontids in all three Paleogene localities

New plesiosaur specimens from the Maastrichtian Phosphates of Morocco and their implications for the ecology of the latest Cretaceous marine apex predators

International audienceSeveral clades of marine tetrapods, including the apex predators mosasaurs and plesiosaurs, disappeared during the mass extinction at the end of the Cretaceous, about 65 My ago. The extreme fossil richness of the Maastrichtian Phosphates of Morocco provides insights into the systematic diversity of the latest mosasaurs where about ten species are known. However, data of the coeval plesiosaurs are comparatively scarce. Up to now, only one species, the elasmosaurid Zarafasaura oceanis, is known. Here we describe new elasmosaurid ple-siosaur post-cranial material from the Maastrichtian of the Oulad Abdoun Basin (Morocco) that provides new data about the taxonomical and morphological diversity of plesiosaurs in this area. Most of the new material consists of vertebrae that likely belong to a unique elasmosaurid taxon and differ from all other elasmosaurids documented so far. As Zarafasaura is known only from cranial material, it cannot be determined whether the new material may be assigned to this taxon. The new material shows that the latest Cretaceous plesiosaurs in this low latitude area (about 20°N) were rather gracile, most likely piscivorous taxa that occupied ecological niches similar to those of rather small mosasaurs (e.g., Halisaurus and "Platecarpus" ptychodon) but distinct from those of most coeval large mosasaur taxa. These plesiosaur fossils are also remarkable in that they consist of both juvenile and adult specimens, suggesting limited segregation between individuals of different ontogenetic stages, a feature that might be attributed to upwelling-related, high nutrient input and food availability in this area during the Maastrichtian. Moreover, the possible occurrence, with older specimens, of a neonate specimen-one among the very few known worldwide-suggests a possible social structure organization. The new data contribute to increase our understanding of Late Cretaceous plesiosaur biodiversity and provide new insights into the ecology of latest Cretaceous marine apex predators

Figure 17 in A new species of Halisaurus from the Late Cretaceous phosphates of Morocco, and the phylogenetical relationships of the Halisaurinae (Squamata: Mosasauridae)

Figure 17. Strict consensus tree of six most parsimonious trees (270 steps) showing the phylogenetic relationships of Halisaurus arambourgi sp. nov. and Halisaurinae among Mosasauridae.Published as part of <i>Bardet, Nathalie, Suberbiola, Xabier Pereda, Iarochene, Mohamed, Bouya, Baadi & Amaghzaz, Mbarek, 2005, A new species of Halisaurus from the Late Cretaceous phosphates of Morocco, and the phylogenetical relationships of the Halisaurinae (Squamata: Mosasauridae), pp. 447-472 in Zoological Journal of the Linnean Society 143 (3)</i> on page 463, DOI: 10.1111/j.1096-3642.2005.00152.x, <a href="http://zenodo.org/record/10114628">http://zenodo.org/record/10114628</a&gt

<i>Maroccosuchus zennaroi</i> (Crocodylia: Tomistominae) from the Eocene of Morocco: phylogenetic and palaeobiogeographical implications of the basalmost tomistomine

<div><p><i>Maroccosuchus zennaroi</i> Jonet & Wouters, 1977 from the Ypresian of the Oulad Abdoun Basin (Morocco) is described in detail based on numerous and well-preserved specimens. A phylogenetic analysis including 64 ingroup taxa and 238 characters reveals that <i>M. zennaroi</i> is the basalmost tomistomine. This clade is supported by 10 unambiguous synapomorphies, while only two – both related to the snout shape and observed in gavialoids – support a closer relationship between <i>Kentisuchus spenceri</i> and later tomistomines. Their absence in <i>M. zennaroi</i> could reflect its intermediate morphology between basal crocodyloids and longirostrine tomistomines. This clearly indicates a Lower Eocene, and no older than Late Palaeocene age for the tomistomine emergence, questioning the Late Eocene, Oligocene and Miocene ages proposed for <i>Gavialis</i>–<i>Tomistoma</i> divergence by molecular analyses. Considering this analysis, the biogeographical history of the tomistomines is evaluated. This history begins in western Tethys during the Lower Eocene or latest Palaeocene, with <i>M. zennaroi</i> followed by several West European tomistomines. The Tethys becomes the centre of dispersal to North America, Africa and Asia. The phylogenetic analysis also suggests at least two independent dispersals from the Tethyan area to Asia, with the extant <i>Tomistoma schlegelii</i> more closely related to European Miocene forms in the first instance, and <i>Toyotamaphimeya machikanense</i> and <i>Penghusuchus pani</i> more closely related to the North American <i>Thecachampsa</i> in the second instance. However, the small number of remains from the Oligocene and Late Eocene does not allow a clear date of divergence and dispersal routes to be ascertained.</p></div

Nouvelles données sur Phosphatherium escuilliei (Mammalia, Proboscidea) de l'Éocène inférieur du Maroc, apports à la phylogénie des Proboscidea et des ongulés lophodontes

Gheerbrant, Emmanuel, Sudre, Jean, Tassy, Pascal, Amaghzaz, Mbarek, Bouya, Baâdi, Iarochène, Mohamed (2005): Nouvelles données sur Phosphatherium escuilliei (Mammalia, Proboscidea) de l'Éocène inférieur du Maroc, apports à la phylogénie des Proboscidea et des ongulés lophodontes. Geodiversitas 27 (2): 239-333, DOI: 10.5281/zenodo.537522