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Additional specimens of sudamericid (Gondwanatheria) mammals from the Early Paleocene of Argentina

The extinct, Cretaceous–Paleogene Gondwanatherians have previously been considered to be early xenarthrans, multituberculates and more recently Mammalia incertae sedis. However, the phylogenetic relationships of Gondwanatheria have yet to be resolved. In this paper, additional dental specimens of the gondwanatherian Sudamerica ameghinoi from the Early Paleocene Salamanca Formation of Argentina are described. These specimens provide additional information on Gondwanatheria affinities, sudamericid morphology and help support earlier hypotheses on Sudamerica dental formula and tooth categories.

A new spinicaudatan genus (Crustacea: 'Conchostraca') from the Late Cretaceous of Madagascar

A new spinicaudatan genus and species, Ethmosestheria mahajangaensis gen. et sp. nov., is described from the Anembalemba Member (Upper Cretaceous, Maastrichtian) of the Maevarano Formation, Mahajanga Basin, Madagascar. This is the first spinicaudatan reported from the post-Triassic Mesozoic of Madagascar. The new species is assigned to the family Antronestheriidae based on the cavernous or sievelike ornamentation on the carapace.

Three-dimensional modelling and analysis of dinosaur trackways

Light Detection And Range (LiDAR) imaging provides a means to model the 3D geometry of fossil tracks in the field with high accuracy. This represents a considerable advance for the science of vertebrate ichnology in which traditional field methods suffer from a significant degree of abstraction and lack the resolution required to interpret tracks quantitatively. Three-dimensional LiDAR models provide additional morphometric information and allow the application of new analytical tools unique to the digital environment.

The oldest therocephalians (Therapsida, Eutheriodontia) and the early diversification of Therapsida

The oldest records of mammal-like therapsids in Laurasia are from the Ocher Complex of Russia and the Xidagou Formation of China, whereas in Gondwana they are restricted to the Eodicynodon Assemblage Zone, Beaufort Group of the South African Karoo. This fauna, which is relatively depauperate when compared with younger assemblage zones from the Karoo, shows an amazing diversity of therapsids including: dinocephalians (already represented by the carnivorous anteosaurids and the herbivorous tapinocephalids), anomodonts (including dicynodonts), gorgonopsians, and therocephalians.

A new, large ornithomimid from the Cretaceous Dinosaur Park Formation of Alberta, Canada: implications for the study of dissociated dinosaur remains

Only two ornithomimid genera, Ornithomimus and Struthiomimus, are currently known from the Upper Cretaceous of North America. However, a number of ornithomimid elements from Alberta's Dinosaur Park Formation (Upper Campanian), cannot be assigned to either Ornithomimus or Struthiomimus. These bones, including a frontal, caudal vertebrae, and unguals of the manus and the pes, come from animals significantly larger than any previously known Judithian ornithomimid.

The aerodynamics of the British Late Triassic Kuehneosauridae

The Kuehneosauridae (Late Triassic, Britain, USA) had remarkable adaptations, most notably their elongate mid-dorsal ribs that were presumably covered with a skin membrane in life. These lateral 'wings' have always been linked with some form of gliding adaptation, but quantitative studies have been limited. Here, we provide a thorough aerodynamic analysis of both genera of British kuehneosaurids based on theory and on experiments with life-sized models in a wind tunnel.

A new amphicyonine (Carnivora: Amphicyonidae) from the Upper Miocene of Batallones-1, Madrid, Spain

The vertebrate community of the late Miocene locality of Batallones-1, Madrid Province, Spain, is mainly composed of mammals of the order Carnivora, which represents 98 per cent of the total number of macro-mammal fossils. Here, we describe craniodental remains of approximately 12 individuals of a new, highly specialized member of the Amphicyonidae, previously assigned to Amphicyon sp. cf. A. castellanus. A phylogenetic analysis of Amphicyoninae shows that this new form, named Magericyon anceps gen. et sp.

A new Semlikiichthys fish (Teleostei, Perciformes) from the Upper Miocene of Chad: fossil record and palaeobiogeographical implications

Semlikiichthys is a fossil genus of perciform fish from the Neogene continental deposits of Africa. Until now, it was known in Mio-Pliocene sites of the Great Lake Region and of the River Nile by a single species, S. rhachirhinchus. Here, we describe new Semlikiichthys material recovered from Central Africa (Upper Miocene of Toros-Menalla, western Djurab, Chad), and compare it to S. rhachirhinchus, which is the only known species of the genus, and also with Lates niloticus, which is the fish in African Neogene deposits that most closely resembles it.

A leafcutter bee trace fossil from the Middle Eocene of Patagonia, Argentina, and a review of megachilid (Hymenoptera) ichnology

The ichnospecies Phagophytichnus pseudocircus isp. nov. is described to include trace fossils characterized by leaf-margin excisions showing eccentricity values of 0.35–0.65 and more than 270 degrees of an arc, a non cuspate margin and vein stringers or necrotic flaps of tissue along the margin.

A cladistic analysis among trilophodont gomphotheres (Mammalia, Proboscidea) with special attention to the South American genera

The trilophodont gomphothere group is a monophyletic group of genera separated from other proboscideans by one synapomorphy, the presence of trefoil-shaped wear patterns on the occlusal surfaces of their teeth. These wear patterns vary from being just a single trefoil, through double trefoils, to more complex combinations of trefoils. They are present in all of the genera studied here. Our cladistic analysis makes use of 12 genera as terminal taxa. It was performed using 43 cranial, dental and postcranial morphological characters.
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