Annales de Paleontologie最新文献

Jurassic (Oxfordian) crinoids from the Brno area (Czech Republic) are described in details for the first time. A rich crinoid assemblage consisting of cups, isolated cup elements, brachial plates, columnals, pluricolumnals, and cirrals is assigned to isocrinids Isocrinus amblyscalaris (Thurmann), Balanocrinus subteres (Münster), B. pentagonalis (Goldfuss), Isocrinida indet., comatulid Hrabalicrinus zitti gen. et sp. nov., cyrtocrinids Lonchocrinus sp., Cyrtocrinus cf. nutans (Goldfuss), Pilocrinus moussoni (Desor), Tetracrinus moniliformis Münster, Cyrtocrinida indet., and millericrinids (Millericrinida indet.). Crinoids already mentioned from the Jurassic strata of the Czech Republic are subsequently revised. Apart from the isolated remains of Isocrinida, Millericrinida, and Thiolliericrinida, the presence of any other taxon reported from this area should be treated with extreme caution. A rare example of non-regenerative columnal healing (the so-called callus) in I. amblyscalaris is also described. Based on sedimentology and microfacies, the Jurassic limestones were deposited in various palaeoenvironments of upper carbonate platform and shelf lagoon (0 to > 50 m palaeodepth).

In the eastern Saharan Atlas, particularly in the northern area of Tebessa Province (NE Algeria), the widely outcropping Cenomanian strata display a highly diversified macrofauna, among which bivalves are prominently represented. Twenty-eight bivalve species are here reported for the first time from the Cenomanian of Hameimat Massifs. Based on the stratigraphic distribution of these bivalves, five bivalve zones were recognized, i.e., Costagyra olisiponensis - Gyrostrea delettrei, Rhynchostreon suborbiculatum - Exogyra conica, Ceratostreon flabellatum, Ilymatogyra africana, and Pycnodonte vesicularis vesiculosa - Rastellum carinatum zones. Correlation to the ammonite biozones of the same region as follows: the Costagyra olisiponensis - Gyrostrea delettrei and the Rhynchostreon suborbiculatum - Exogyra conica zones occur respectively in the Sharpeiceras schlueteri and Mantelliceras saxbii subzones of the lower Cenomanian Mantelliceras mantelli Zone. The Ceratostreon flabellatum Zone is correlated with the middle Cenomanian Acanthoceras rhotomagense Zone. The Ilymatogyra africana Zone is correlated with the upper Cenomanian Calycoceras naviculare and the Metoicoceras geslinianum zones. Finally, the Pycnodonte vesicularis vesiculosa - Rastellum carinatum Zone represents the uppermost Cenomanian. Detailed analysis of biometrical and morphological features of these bivalve specimens provides the most reliable tool within the scope of palaeo-environmental reconstitution and the many palaeo-ecological variables that had driven the development and distribution of these macro-invertebrates. Comparison of these new data to those of adjacent south Tethyian areas supports the homogeneity of the Cenomanian bivalve faunas. Such an affinity underlines more vividly the favorable marine communications and currents driving the geographic dispersal of these bivalves during the Cenomanian.

Following our fieldwork in Paleogene deposits of Togo, we herein report cranial as well as postcranial elements belonging to the family Dyrosauridae. This assemblage is dated to the Late Paleocene (Thanetian) from two quarries in southern Togo. The specimens include a partial skull presenting two large supratemporal fossae and a massive occipital condyle; long and slender isolated teeth; amphicoelous vertebrae including several articulated ones; and two osteoderms devoid of carina. The morphology of the partial skull reveals similarities with some African longirostrine forms such as Rhabdognathus spp., although this attribution cannot be confirmed. Longirostrine forms, known in the late Paleocene and early Eocene of the Iullemmeden basin (Nigeria, Niger, Mali, Algeria) and in the phosphates of Morocco and Tunisia, is only represented in Thanetian levels in Togo. Different palaeoenvironmental settings seem to have characterized the various African basins during the lower Eocene, with consequences for the geographic distribution of dyrosaurids. These dyrosaurid remains confirm the presence of the family in Togo during the Paleocene and underline the fossiliferous potential of the coastal sedimentary basin in Togo and in the bay of Benin.

Earliest cetaceans (whales) originated from the early Eocene of Indo-Pakistan, but the group dispersed through most of the oceans of the planet by the late middle to late Eocene. This late Eocene global distribution indicates that important dispersal events took place during the middle Eocene (Lutetian), a globally undersampled time interval that is well documented in the Togolese phosphate series. We report here the first discovery of a partial cetacean cranium from middle Eocene deposits of Togo (West Africa). A 3D model of the cranium and teeth was reconstructed in order to reveal hidden anatomical features. The dental and cranial characteristics of the Togolese specimen recall those of protocetid taxa described in Africa, Asia, and North America, but also display significant differences. In particular, we show that the new specimen shares a number of morphological features with the Togolese taxon Togocetus. Such a hypothesis is further supported by a cladistic analysis including 45 taxa and 167 morphological characters, which recovers the new specimen close to Togocetus as the first offshoot of protocetids. Phylogenetic analysis including all the protocetids remains of Kpogamé confirms the singular diversity of the Togolese phosphate basin, and enables to examine potential connections with faunas from contemporaneous localities in Africa.

A new species of pelecinid wasp, Eopelecinus marechali sp. nov., is described and figured from mid-Cretaceous Burmese amber based on a single well-preserved female specimen. Contrary to Eopelecinus inopinatus Jouault et al., 2020a, unique other Eopelecinus known from this deposit, the new species is based on a complete female specimen. This discovery confirms that the Pelecinidae were highly diverse during the Cretaceous and highlights the underestimated diversity of the genus Eopelecinus in Burmese amber biota. Eopelecinus marechali sp. nov. differs from all other Eopelecinus species by its unique metasomal ratio. A summary on the fossil pelecinid species with distributions and ages is provided. Based on the particular geological history of the West Burmese Terrane and the fossil record of the family, the hypothesis of an Asian origin of the family is discussed. The records of Eopelecinus in both Laurasia and Burmese amber biota, during the mid-Cretaceous, suggest that possible transfers of fauna have taken place between these two geological blocks.

A large sample of mecochirid lobsters (Crustacea, Decapoda, Mecochiridae) has been recently collected from the early Barremian (Early Cretaceous) of Lebanon. The studied specimens are described as Meyeria libanotica sp. nov. The genus Meyeria M’Coy, 1849 is also revised and new combinations are proposed for two species: Meyeria bartholomaii (Jell, Woods, and Cook, 2017) comb. nov. (Aptian, Australia), and Meyeria rostrata (Collins and Rasmussen, 1992) comb. nov. (Campanian–Maastrichtian, Greenland). The stratigraphic range and the palaeogeographic distribution of Meyeria are consequently recognized to spread from the Oxfordian (Late Jurassic) to the Maastrichtian (Late Cretaceous) and from Australia to Greenland, passing by Europe, respectively.

A stratigraphic, palaeontological and sedimentological study was carried out in the red beds cropping out on the left side of Oued Tafarahit, south-east of the Ksour Mountains (Algeria). The studied succession consists of a non-marine fining-upward detrital formation, including microconglomerate, sandstone and clay beds, which were previously attributed to the Cenozoic sensu lato, since no palaeontological evidence was available. Sedimentology suggests deposition in a fluvial environment. The clayey levels yielded the assemblage formed by the charophytes Peckichara atlasensis, Maedleriella cristellata, Nitellopsis (Tectochara) thaleri, Grovesichara sp., and Lamprothamnium papulosum and the ostracods Neocyprideis meguerchiensis, Herpetocypris? sp. and Cyprinotus? sp. This assemblage allows constraining the age of the detrital series from Oued Tafarahit to the Ypresian. Ostracods are typical of freshwater to euryhaline environments. The freshwater taxa (Herpetocypris? sp. and Cyprinotus? sp.) would indicate phases of desalinisation during periods of flood. However, the brackish water species (Neocyprideis meguerchiensis) is characteristic of saline phases related to low water table periods. Moreover the charophyte and ostracod assemblage confirms a close palaeobiogeographic relationship between North Africa and Southern Europe during the Lower Eocene.