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The early evolution of dinosaurs is documented by abundant postcranial material, but cranial material is much rarer and comparisons of cranial features among early dinosaurs are limited to only a few specimens. Here, we fully detail the osteology of the unusual early-diverging dinosaur Daemonosaurus chauliodus from the latest Triassic Coelophysis Quarry in northern New Mexico, USA. The taxon possesses a unique and curious suite of character states present in a variety of early dinosaurs, and the morphology of D. chauliodus appears to link the morphology of Herrerasaurus with that of later diverging eusaurichians. Our phylogenetic analyses places D. chauliodus at the base of dinosaurs and our interpretation of the unusual mix of character states of D. chauliodus does not lead to a firm conclusion about its nearest relationships or its implications for the evolution of character state transitions at the base of Dinosauria. The combination of character states of D. chauliodus should not be ignored in future considerations of character evolution in early dinosaurs. As one of the last members of the earliest radiation of saurischians in the Carnian–early Norian, D. chauliodus demonstrates that members of the original diversification of dinosaurs survived until nearly the end of the Triassic Period. [ABSTRACT FROM AUTHOR]

The group of Permo-Carboniferous tetrapods known as Recumbirostra have recently been hypothesized to represent the earliest radiation of fossorial reptiles. Therefore, understanding the anatomy and diversity of this clade is essential to understanding the origin and early evolution of amniotes. Here, we redescribe the diminutive 'microsaur' Odonterpeton triangulare from the Moscovian-age deposit of Linton, Ohio, revealing new details on the structure of the cranium and palate, including the presence of a conspicuous transverse flange of the pterygoid, which is a feature traditionally associated with early amniotes. Phylogenetic analysis supports the placement of Odonterpeton triangulare within Recumbirostra as sister taxon to the recently described Joermungandr bolti from the slightly older Mazon Creek, Illinois, Lagerstätte. Together, these two diminutive recumbirostrans are placed in an Odonterpetidae clade. Furthermore, we provide a discussion of newly recognized anatomical features in recumbirostrans and discuss major features of recumbirostran phylogeny. We designate a new recumbirostran clade, Chthonosauria (Brachystelechidae + Molgophidae), which is supported by a number of shared derived cranial features. [ABSTRACT FROM AUTHOR]

The holotype of cf. Halticosaurus orbitoangulatus Huene, 1932, comprises an incomplete and macerated but associated skull of an archosaurian reptile from the middle (second) Stubensandstein (middle Löwenstein Formation; Upper Triassic: Norian) of Baden-Württemberg, Germany. It was originally interpreted as a theropod dinosaur but more recently it has been suggested that this taxon has crocodylomorph affinities. Detailed preparation of the holotype of cf. H. orbitoangulatus has revealed much new anatomical information and permitted reassessment of its affinities. The maxilla lacks both a distinct antorbital fossa and a medial bony lamina bordering the antorbital fenestra. The lateral surface of the dentary bears a pronounced horizontal ridge. The squamosal differs from that of basal crocodylomorphs in being L-shaped rather than arcuate in dorsal view, lacking a dorsolateral overhang, and lacking an interlocking contact with the paroccipital process as, for example, in the basal crocodylomorph Saltoposuchus connectens from the same horizon and locality. Phylogenetic analysis placed cf. H. orbitoangulatus amongst loricatan pseudosuchians (but not amongst Crocodylomorpha) rather than amongst theropod dinosaurs. The holotype of cf. H. orbitoangulatus represents a previously unrecognized taxon of loricatan pseudosuchian, which is here named Apatosuchus orbitoangulatus and set apart from other known Norian-age non-crocodylomorph loricatans by its apparently much smaller size. © 2013 The Linnean Society of London [ABSTRACT FROM AUTHOR]

This paper presents a detailed description of the skull and part of the mandible of the crocodyliform reptile Hamadasuchus rebouli from the Kem Kem beds (Upper Cretaceous: Albian–Cenomanian) of south-eastern Morocco. This taxon of deep-snouted ziphodont crocodyliform can be diagnosed by a number of autapomorphies. Phylogenetic analysis of a diverse array of crocodylomorph taxa found strong support for a clade comprising H. rebouli, Peirosauridae, and Sebecus. The name Sebecia nom. nov. is proposed for this grouping, which is diagnosed by numerous characters, including the participation of the quadratojugal in the mandibular condyle. The distribution of this diverse and long-lived clade lends further support to the biogeographical hypothesis that faunal connections existed between Africa and South America well into mid-Cretaceous times. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 533–567. [ABSTRACT FROM AUTHOR]

Description of new and re-examination of previously described cranial remains of Prolacerta broomi Parrington allows reappraisal of the structure of the skull in this basal archosauromorph reptile. The ventral margin of the premaxilla is slightly deflected, and there is a relatively large lateral foramen in the maxilla that is bounded anteriorly by the premaxilla; both features are shared with the basal rhynchosaur Mesosuchus and the basal archosauriform Proterosuchus. Implantation of the marginal dentition is ankylothecodont: the teeth are rooted relatively deeply, bounded lingually by a deep wall of the jaw, and anchored to the jaw by bone of attachment. The pineal foramen varies in size from little more than a scar in the interparietal suture to a suboval opening several millimetres in diameter. Contrary to previous claims, the skull roof in Prolacerta was akinetic and quadrate mobility (streptostyly) was absent. Phylogenetic analysis of a previously published data matrix, modified by the addition of new anatomical data and reinterpretation of some characters, corroborates the hypotheses of the polyphyly of Prolacertiformes (Protorosauria) and of a close relationship between Prolacerta and Archosauriformes. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 140, 335–351. [ABSTRACT FROM AUTHOR]

In the present paper, we provide a comprehensive revision of the large-sized neosuchians Kansajsuchus and ' Turanosuchus ' from the Late Cretaceous of Central Asia. Kansajsuchus extensus from the Kansai locality of the Yalovach Formation, Tadzhikistan, is confirmed as a valid taxon. Previously hypothesized goniopholidid affinities of Kansajsuchus are not supported. Our phylogenetic analyses found this taxon as a derived member of the family-level taxon Paralligatoridae. With a dorsal cranial length of 70–80 cm and a total body length reaching 5–7 m, Kansajsuchus extensus is among the largest known paralligatorids and derived neosuchians in general. The large-sized neosuchian from the Shakh Shakh locality of the Bostobe Formation, Kazakhstan, previously identified as Kansajsuchus spp. ' Turanosuchus aralensis ', or Neosuchia indet. with allegedly goniopholidid affinities, is a paralligatorid closely related to K. extensus. The taxonomic composition, internal relationships and geographical distribution of Paralligatoridae are reconsidered. Paralligatoridae is an endemic clade from the Cretaceous of Asia comprising four recognized genera (Paralligator, Shamosuchus, Rugosuchus and Kansajsuchus), which is characterized by the unique suite of osteodermal features (paravertebral osteoderms with high dorsal keels restricted to posterior margins, arranged in more than two rows and lacking anterolateral processes). [ABSTRACT FROM AUTHOR]