The early to middle Selandian fossiliferous Orp Sand Member of the Heers Formation in Belgium has regularly been excavated at its type-locality Maret for its rich and diversified selachian fauna. Among the abundant vertebrate remains, extremely rare mammal specimens have been found. Three isolated teeth have been published previously, all with uncertain affinities. The purpose of this study is to present new specimens from the same deposits, including a small well-preserved dentary of an adapisoriculid attributable to “Afrodon” germanicus, a fragmentary upper molar, referred to Berrulestes sp., and a premolar of a large arctocyonid. Among the previous specimens we identified Arctocyonides cf. weigelti. The adapisoriculid dentary offers new clues that allow transferring “Afrodon” germanicus to the genus Bustylus. The five mammal taxa from Maret indicate an age intermediate between reference-levels MP1-5 of Hainin, Belgium and MP6 of Cernay, France and present the greatest correlation with the rich Walbeck fauna in Germany. The deposits from Walbeck were usually thought to be slightly older than the late Thanetian deposits of Cernay. We infer here that the age of Walbeck is likely to be Selandian. The strong differences observed between Hainin on the one hand, and Walbeck and Cernay on the other hand, document a dispersal event from North America to Europe around the Danian-Selandian boundary.
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New coleoid cephalopods, assignable to the order Sepiida, are recorded from the Selandian/Thanetian boundary interval (Middle to Upper Paleocene transition, c. 59.2 Ma) along the southeastern margin (Toshka Lakes) of the Western Desert in Egypt. The two genera recognised, Aegyptosaepia n. gen. and ?Anomalosaepia Weaver and Ciampaglio, are placed in the families Belosaepiidae and ?Anomalosaepiidae, respectively. They constitute the oldest record to date of sepiids with a ‘rostrum-like’ prong. In addition, a third, generically and specifically indeterminate coleoid is represented by a single rostrum-like find. The taxonomic assignment of the material is based on apical parts (as preserved), i.e., guard, apical prong (or ‘rostrum-like’ structure), phragmocone and (remains of) protoconch, plus shell mineralogy. We here confirm the shell of early sepiids to have been bimineralic, i.e., composed of both calcite and aragonite. Aegyptosaepia lugeri n. gen., n. sp. reveals some similarities to later species of Belosaepia, in particular the possession of a distinct prong. General features of the phragmocone and protoconch of the new form are similar to both Belocurta (Middle Danian [Lower Paleocene]) and Belosaepia (Eocene). However, breviconic coiling and the presence of a longer ventral conotheca indicate closer ties with late Maastrichtian–Middle Danian Ceratisepia. In this respect, Aegyptosaepia n. gen. constitutes a link between Ceratisepia and the Eocene Belosaepia. The occurrence of the new genus near the Selandian/Thanetian boundary suggests an earlier origin of belosaepiids, during the early to Middle Paleocene. These earliest known belosaepiids may have originated in the Tethyan Realm. From northeast Africa, they subsequently spread to western India, the Arabian Plate and, probably via the Mediterranean region, to Europe and North America.
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