Numerous fossil localities were investigated in western central Africa during the Belgian expeditions that started in the 19th century. At least 47 localities were excavated or analyzed in the framework of Edmond Dartevelle’s paleontological expeditions of 1933 and 1937-1938, producing a large and unique collection of Mesozoic-Cenozoic vetebrates from the margin of the Congo Basin along the coastal area of Angola to Gabon. Among them, snake vertebrae from the marine Paleocene-Eocene Landana section, Cabinda enclave, Angola have been referred to the aquatic snake Palaeophis aff. typhaeus. New investigation of the old Dartevelle’s collections has led to relocation of a few undescribed snake vertebrae from Landana and the nearby locality of Sassa Zao, permitting a revision of Palaeophis aff. typhaeus. The results of this work indicate that all specimens from Landana originate from the same stratigraphic level (layers 31-32) and are of Lutetian age based on the rich associated elasmobranch fauna. The locality of Sassa Zao is also Lutetian based on elasmobranchs that are similar to those of layer 32 of Landana. All of the vertebrae, ten in total, can be attributed to a single large species of Palaeophis. The maximum width across the prezygapophyses is 35 mm and the maximum length of the centrum is 27 mm. The weak lateral compression of trunk vertebrae, low development of the pterapophyses, diapophyses not very low, and the marked lateral projection of the zygapophyses indicate that this species belongs to the ‘primitive’ grade of Palaeophis and thus differs from species of the ‘advanced’ group such as P. casei, P. ferganicus, P. littoralis, P. toliapicus, P. typhaeus, P. grandis, P. tamdy, P. nessovi, and P. udovichenkoi. Among ‘primitive’ grade species, it differs from the giant P. colossaeus by smaller size, proportionally longer vertebrae, the cotyle and condyle more oval in shape, and the zygosphene not larger than the cotyle; from P. africanus by the neural spine that does not approach the zygosphene and shorter hypapophyses that are not prolonged by a ventral carina; from P. vastaniensis, P. virginianus, and P. zhylan by less depressed vertebrae. In size and morphology it most closely resembles P. maghrebianus but differs by more developed hypapophyses and paradiapophyses that do not extend over the cotyle posteriorly. This new species was apparently poorly adapted to aquatic life and was more closely related to the North African Ypresian P. maghrebianus than to West African Lutetian species. Grant Information This abstract is a contribution to the project BR/121/A3/PalEurAfrica funded by the Belgian Science Policy Office.
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RBINS Staff Publications 2016
The Crocodylia include all modern crocodiles, alligators, caimans and gharials, and their extinct relatives. They are an ancient lineage that originated around 70 million years ago. Recently, the field of crocodylian paleontology has experienced a rise in attention from researchers, however, much is still unknown about the early evolution of this group. Our research describes newly discovered fossil material comprised of a small crocodylian skull and associated partial lower jaw of early Paleocene age. It was discovered during a Belgian-Chinese expedition in Qianshan Basin, Anhui Province, China, as part of a bilateral cooperation project between the Royal Belgian Institute of Natural Sciences and the Institute of Botany of the Chinese Academy of Sciences. In the present study, the fossil material is formally described for the first time. Micro-CT scans are made to visualize internal anatomical structures, as well as characters hidden by the sediment. A comprehensive morphological study is executed, revealing that the specimen is a juvenile. It likely constitutes a new species and genus, as it differs from other crocodyloids by several autapomorphies. A phylogenetic analysis based on morphological characteristics reveal that this specimen is the most basal taxon among Crocodyloidea, a group that comprises all species more closely related to modern crocodiles than to modern alligators, caimans, or gharials. Although it is not the oldest crocodyloid ever reported, it is the earliest crocodyloid in Asia. Moreover, its basal phylogenetic position implies that it is part of an ancient ghost lineage of crocodyloids that had already been around in Asia for a longer time. The presence of crocodyloid remains in the Late Cretaceous of North America and the late Paleocene of Europe suggests that crocodyloids may have migrated there from Asia early on in their evolutionary history.
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RBINS Staff Publications 2021
