Ceratosuchops Inferodios

''Ceratosuchops'' (meaning "horned crocodile face") is a genus of spinosaurid from the Early Cretaceous (Barremian) of Britain.

Discovery and naming

The holotype remains of this taxon consist of IWCMS 2014.95.5 (premaxillary bodies), IWCMS 2021.30 (a posterior premaxilla fragment), and IWCMS 2014.95.1-3 (a nearly complete braincase). These, in addition to a referred right postorbital (IWCMS 2014.95.4), were recovered from rocks in Chilton Chine of the Wessex Formation.

In 2021, ''Ceratosuchops inferodios'' was named and described by a team of paleontologists including Chris Barker, Darren Naish, David Hone and others. The specific name means "hell heron", in reference to the ecology presumed by the research team.

Classification

In their phylogenetic analysis, Barker ''et al.'' (2021) recovered ''Ceratosuchops'' within the Baryonychinae, as the sister taxon to the coeval ''Riparovenator''. They are, in turn, in a clade containing ''Suchomimus'', which they name Ceratosuchopsini.

In 2023, Sereno and colleagues tentatively combined ''Ceratosuchops'' and ''Riparovenator'' into a single taxonomic unit for their phylogenetic analysis. They reason that the different features between the two taxa could be attributed to individual variation, citing the cranial variation present in specimens of ''Allosaurus fragilis''. Some of their supposed distinguishing features are also seen in parts of the braincase of ''Suchomimus'', their closest relative. The results of their phylogenetic analysis (with ''Ceratosuchops'' and ''Riparovenator'' scored together) yielded similar results to those of Barker ''et al.'' (2021), with the Wessex baryonychine fossils recovered as the sister taxon to ''Suchomimus''.

Palaeobiology

A 2023 study by Barker and colleagues based on CT scans of the braincases of ''Ceratosuchops'' and ''Baryonyx'' found that the brain anatomy of these baryonychines was similar to that of other non-maniraptoriform theropods. Their neurosensory capabilities such as hearing and olfaction (sense of smell) were unexceptional, and their gaze stabilisation less developed than those of spinosaurines, so their behavioural adaptations were probably comparable to those of other large-bodied terrestrial theropods. This suggests that their transition from terrestrial hypercarnivores to semi-aquatic “generalists” during their evolution did not require substantial modification of their brain and sensory systems. This could mean that spinosaurids were either pre-adapted for detection and capture of aquatic prey, or that their transition to semi-aquatic lifestyles only required modifications to the bones associated with the mouth. Their reptile encephalization quotient values imply that the cognitive capacity and behavioural sophistication of baryonychines did not deviate much from that of other basal theropods.

Palaeoenvironment

''Ceratosuchops'' lived in a dry mediterranean habitat in the Wessex Formation, where rivers were home to riparian zones. Like most spinosaurs, it would have fed on available small to medium-sized aquatic and terrestrial prey in these areas.

Other dinosaurs from the Wessex Formation of the Isle of Wight include the theropods ''Riparovenator'', ''Neovenator'', ''Eotyrannus'', '' Aristosuchus'', '' Thecocoelurus'', '' Calamospondylus'', and '' Ornithodesmus'', the ornithopods ''Iguanodon'', ''Hypsilophodon'', and ''Valdosaurus'', the sauropods ''Ornithopsis'', ''Eucamerotus'', and '' Chondrosteosaurus'', and the ankylosaur ''Polacanthus''. Barker and colleagues stated in 2021 that the identification of the two additional spinosaurids from the Wealden Supergroup, ''Riparovenator'' and ''Ceratosuchops'', has implications for potential ecological separation within Spinosauridae if these and ''Baryonyx'' were contemporary and interacted. They cautioned that it is possible the Upper Weald Clay and Wessex Formations and the spinosaurids known from them were separated in time and distance.

It is generally thought that large predators occur with small taxonomic diversity in any area due to ecological demands, yet many Mesozoic assemblages include two or more sympatric theropods that were comparable in size and morphology, and this also appears to have been the case for spinosaurids. Barker and colleagues suggested that high diversity within Spinosauridae in a given area may have been the result of environmental circumstances benefiting their niche. While it has been generally assumed that only identifiable anatomical traits related to resource partitioning allowed for coexistence of large theropods, Barker and colleagues noted that this does not preclude that similar and closely related taxa could coexist and overlap in ecological requirements. Possible niche partitioning could be in time (seasonal or daily), in space (between habitats in the same ecosystems), or depending on conditions, and they could also have been separated by their choice of habitat within their regions (which may have ranged in climate).

References

{{Taxonbar, from=Q108742018

Spinosauridae
Dinosaur genera
Barremian dinosaurs
Wessex Formation
Fossil taxa described in 2021
Taxa named by Darren Naish
Dinosaurs of the United Kingdom