Machimosaurus was a large-bodied genus of teleosaurid crocodylomorph, considered to have been durophagous/chelonivorous, and which frequented coastal marine/estuarine ecosystems during the Late Jurassic. Here, we revise the genus based on previously described specimens and revise the species within this genus. We conclude that there were three European Machimosaurus species and another taxon in Ethiopia. This conclusion is based on numerous lines of evidence: craniomandibular, dental and postcranial morphologies; differences in estimated total body length; geological age; geographical distribution; and hypothetical lifestyle. We re-diagnose the type species Machimosaurus hugii and limit referred specimens to only those from Upper Kimmeridgian–Lower Tithonian of Switzerland, Portugal and Spain. We also re-diagnose Machimosaurus mosae, demonstrate that it is an available name and restrict the species to the uppermost Kimmeridgian–lowermost Tithonian of northeastern France. We re-diagnose and validate the species Machimosaurus nowackianus from Harrar, Ethiopia. Finally, we establish a new species, Machimosaurus buffetauti, for the Lower Kimmeridgian specimens of France and Germany (and possibly England and Poland). We hypothesize that Machimosaurus may have been analogous to the Pliocene–Holocene genus Crocodylus in having one large-bodied taxon suited to traversing marine barriers and additional, geographically limited taxa across its range.

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Teleosaurids were a clade of crocodylomorphs that attained near-global distribution during the Jurassic Period. Within Teleosauridae, one particular sub-clade of durophagous/macrophagous taxa achieved large body sizes and were apex predators in shallow marine environments during the Late Jurassic and Early Cretaceous in Europe and around the coast of the Tethys Seaway. Unfortunately, the origins of this clade are still poorly understood. 'Steneosaurus' obtusidens is a little-studied macrophagous species from the Oxford Clay Formation (Callovian, Middle Jurassic) of the United Kingdom and near Migné-les-Lourdines (middle Callovian) in France. Despite being considered a sister taxon of the Late Jurassic taxon Machimosaurus, the taxonomy of 'S.' obtusidens remains unclear. Although three different synonymies have been proposed (variously a subjective synonym of other taxa), these taxonomic hypotheses have not been based on detailed anatomical comparisons and thus have not been tested. Here we re-describe of the holotype of 'S.' obtusidens, demonstrate that it is indeed a valid taxon, restrict the referred specimens to a fragmentary skeleton, nearly complete skull, and partial rostrum, and establish a new monotypic genus, Lemmysuchus. Our re-description reveals five autapomorphies for L. obtusidens, and nine apomorphic characters that support the tribe Machimosaurini (Lemmysuchus + Machimosaurus).

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The discovery of a new genus and species of gavialoid at the Danian-Thanetian boundary, in the Oulad Abdoun Basin of Morocco, is consistent with an African origin of Gavialoidea. Argochampsa krebsi, n.g. n.sp., exhibits a particular shape of the anterior end of its premaxillae, transversely broad and strongly bent downwards, a shape found in distantly related taxa, such as pholidosaurids and Terminonaris. A phylogenetic analysis, suggests that A. krebsi is a primitive gavialoid, placed with Eogavialis africanum between 'thoracosaurs' (primitive Gavialoidea) and more derived taxa. This analysis supports the previous morphological analysis, which suggests a close relationship of Tomistominae with Crocodylinae, in contrast with the molecular analysis which give a closer relationships between Tomistoma and Gavialis. The marine nature of the layer where Argochampsa comes from is consistent with a marine origin for Argochampsa. This demonstrates the existence of marine adaptation in fossil species of primitive gavialoids, which may explain the dispersal of the fossil gavialoids to South America and Asia during and after the Oligocene.

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A partial crocodilian skeleton, including a well-preserved skull and mandible, from the marine Lower Cenomanian of Normandy (northwestern France) is described as a new genus and species of the family Pholidosauridae (Mesosuchia), Oceanosuchus boecensis. Diagnosis for genus and species: Mesorostrine pholidosaurid (rostral index 66% as compared with 74% for Terminonaris robusta and 75% for Sarcosuchus imperator, hitherto the least longirostrine species in that family), relatively short mandibular symphysis (11 post-symphysial alveoli), no external mandibular fenestra, prearticular present, paired tuberosities at the base of the cervical vertebral centra.