Abstract The Norwegian Arctic Svalbard archipelago is famous for its prolific record of Early–Middle Triassic vertebrate fossils. These represent mainly marine amniotes, together with sharks, bony fishes and temnospondyl amphibians, the latter providing an important faunal correlate with coeval assemblages from the Danish autonomous region of Greenland. However, substantial biostratigraphical gaps exist in the Upper Triassic strata of Svalbard, which are marked by pronounced facies shifts from marine to deltaic systems and intermittent depositional hiatuses. These are accompanied by a dearth of documented vertebrate remains, a notable exception being the partial skull of the capitosaurian Capitosaurus polaris and a few isolated stereospondylian intercentra probably from the middle–late Carnian De Geerdalen Formation of Spitsbergen. Reassessment of this material, which incorporates the only undisputed capitosaurian fossil from Svalbard, indicates affinity with Cyclotosaurus , known elsewhere from the late Norian–early Rhaetian Fleming Fjord Formation of Greenland. The Scandinavian Arctic temnospondyls constituted components of sympatric assemblages that inhabited the Boreal margin of Pangaea throughout the Triassic.

Abstract Mesozoic dinosaur fossils are exceptionally rare in Scandinavia. The Swedish record is typically depauperate, with the Kristianstad Basin of Skåne (Scania) yielding all of the known fossils from Swedish Cretaceous strata. Although highly fragmentary, these body remnants are important because they provide evidence of a relatively diverse fauna, including previously recognized hesperornithiform birds and leptoceratopsid ceratopsians, as well as indeterminate ornithopods that are confirmed here for the first time. In this paper, we describe three phalanges (from Åsen) and an incomplete right tibia (from Ugnsmunnarna) from the Kristianstad Basin. One of the phalanges appears to pertain to a leptoceratopsid ceratopsian, providing further evidence of these small ornithischians in the Cretaceous sediments of Sweden. The other two phalanges are interpreted as deriving from small ornithopods similar to Thescelosaurus and Parksosaurus . The tibia appears to represent the first evidence of a non-avian theropod dinosaur in the Cretaceous of Sweden, with a previous report of theropod remains based on fish teeth having been corrected by other authors. The remains described herein provide important additions to the enigmatic dinosaurian fauna that inhabited the Fennoscandian archipelago during the latest Cretaceous.

Abstract Although a diverse range of aquatic vertebrates are documented from the Upper Cretaceous (mid-Campanian) marine strata of the Kristianstad Basin in southern Sweden, only chondrichthyans and marine amniotes have been described in detail to date. In contrast, coeval actinopterygians are virtually unreported, yet their remains are extremely abundant at most sampled localities. A comprehensive assessment of these fossils has identified the first Late Cretaceous actinopterygian fauna from the Fennoscandian Shield, incorporating indeterminate lepisosteids, the durophagous pycnodontid Anomoeodus subclavatus , the predatory pachycormid Protosphyraena sp., a large ichthyodectid, pachyrhizodontids resembling Pachyrhizodus , the enchodontid Enchodus cf. gladiolus and indeterminate small teleosts. These taxa are diagnosed mainly from isolated teeth and scales, implying substantial taphonomic loss prior to burial. Moreover, the prolific recovery of actinopterygian skeletal remnants in recent excavations suggests that historical collecting biases, rather than ecological paucity, have contributed to their under-representation in the Swedish Cretaceous record. Palaeobiogeographically, the Kristianstad Basin actinopterygians show compositional resemblance to assemblages from the Northern European Platform and the Western Interior Seaway of North America, advocating distributional communication across the Boreal proto-Atlantic Ocean.