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Crocodylomorpha is the stem-lineage of modern crocodylians and the only pseudosuchian (i.e. crocodylian-line archosaurs) clade that survived the Triassic–Jurassic mass extinction event. Its earliest members, the non-crocodyliform crocodylomorphs, also known as 'sphenosuchians', were terrestrial and mostly small-bodied (<2 m long), although some large-bodied forms are known. Saltoposuchus connectens is one of the first described crocodylomorph species but it remains poorly studied, in part due to its contentious taxonomy. Here, all referred Saltoposuchus specimens are described in detail for the first time and its taxonomy is revised, with additional taxonomic implications for the British crocodylomorph Terrestrisuchus gracilis and the coelophysoid theropod Procompsognathus triassicus. Saltoposuchus connectens is clearly distinguished from Terrestrisuchus gracilis based on both cranial and postcranial features. The phylogenetic analysis finds that Saltoposuchus connectens , Terrestrisuchus gracilis , and Litargosuchus leptorhynchus form a clade of gracile, long-legged crocodylomorphs, identified as Saltoposuchidae Crush 1984. A histological section of a femur reveals highly vascularized fibrolamellar tissue in the second-largest specimen of Saltoposuchus connectens (SMNS 12596), indicating sustained high growth rates. A similar pattern was previously observed in Terrestrisuchus sp. contrasting with slower growth rates in the crocodylomorph Hesperosuchus agilis. These findings suggest that saltoposuchids had a high resting metabolic rate and active lifestyle. [ABSTRACT FROM AUTHOR]

Phytosaurs are a diverse and morphologically distinctive clade of superficially crocodile-like archosauriforms that had a near global distribution during the Late Triassic. Because their remains are among the most abundant vertebrate remains recovered in many Upper Triassic terrestrial formations, phytosaurs are used extensively in long-range biochronological and biostratigraphic correlations. The biochronologically oldest and earliest branching known phytosaurs include an array of nominal species from the early Late Triassic of the United States, Germany, Poland, Morocco, and India that have been synonymized within the genus Paleorhinus, and subsequently used to define a global ' Paleorhinus biochron'. However, recent phylogenetic work suggested that the North American species previously referred to Paleorhinus are paraphyletic. Here, we reassess the systematics and anatomy of putative specimens of Paleorhinus from southern Germany. Two well-preserved basal phytosaur skulls from the Blasensandstein ( Carnian) of Bavaria form the holotypes of Francosuchus angustifrons and Ebrachosuchus neukami, both of which were synonymized with Paleorhinus by previous workers. We demonstrate that Francosuchus angustifrons shares unique synapomorphies with specimens referred to Paleorhinus bransoni from the Late Triassic of Texas, and thus refer the species to Paleorhinus. By contrast, the longirostrine Ebrachosuchus is highly distinctive in morphology, and our new cladistic analysis of Phytosauria demonstrates that it represents a valid taxon that is more closely related to Phytosauridae than to Paleorhinus. We provide the first autapomorphy-based support for a monophyletic but restricted Paleorhinus (supported by a nodal row on the jugal, and low paired ridges on the squamosal) and confirm that previous broader conceptions of Paleorhinus are likely to be paraphyletic. © 2013 The Linnean Society of London [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]

An incomplete skull (SMNS 12352) from the Norian (Late Triassic), found at the same locality (Pfaffenhofen, Germany) as Procompsognathus triassicus, has previously been attributed to either a theropod or a crocodylomorph. The specimen is partially embedded in matrix and, therefore, was CT scanned so that the concealed portion could be visualized and a 3D model could be printed by means of rapid prototyping. Mainly based on the separation between the nasal and the antorbital fossa, the skull likely pertains to an indeterminate basal crocodylomorph (non-Crocodyliformes), which is, however, distinct from Saltoposuchus connectens. [ABSTRACT FROM AUTHOR]