''Torvoneustes'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

metriorhynchid Metriorhynchidae is an extinct family of specialized, aquatic metriorhynchoid crocodyliforms from the Middle Jurassic to the Early Cretaceous period (Bajocian to early Aptian) of Europe, North America and South America. The name Metriorhynchidae ...

thalattosuchian. It is known from skull and postcranial remains found in the Kimmeridge Clay Formation of

Dorset Dorset ( ; archaically: Dorsetshire , ) is a county in South West England on the English Channel coast. The ceremonial county comprises the unitary authority areas of Bournemouth, Christchurch and Poole and Dorset (unitary authority), Dors ...

and

Wiltshire Wiltshire (; abbreviated Wilts) is a historic and ceremonial county in South West England with an area of . It is landlocked and borders the counties of Dorset to the southwest, Somerset to the west, Hampshire to the southeast, Gloucestershire ...

, England, and also from

Oaxaca Oaxaca ( , also , , from nci, Huāxyacac ), officially the Free and Sovereign State of Oaxaca ( es, Estado Libre y Soberano de Oaxaca), is one of the 32 states that compose the political divisions of Mexico, Federative Entities of Mexico. It is ...

, Mexico . The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

skull of the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

was initially assigned to the species '' Metriorhynchus superciliosus''. Postcranial remains were later discovered from the same quarry as the skull, and then these specimens were recognised as belonging to a new species of '' Dakosaurus'', as ''D. carpenteri''. The species was named to honour Simon Carpenter, an amateur geologist from Frome in Somerset, who discovered the fossils. ''Dakosaurus carpenteri'' was later reassigned to the genus ''

Geosaurus ''Geosaurus'' is an extinct genus of marine crocodyliform within the family Metriorhynchidae, that lived during the Late Jurassic and the Early Cretaceous. ''Geosaurus'' was a carnivore that spent much, if not all, its life out at sea. No ''Geosa ...

'' in 2008. Two years later, it was assigned to its own genus, ''Torvoneustes''. When ''T. carpenteri'' was considered a species of ''Dakosaurus'', its relatively long snout and smaller, more numerous teeth were thought to be features retained from more basal metriorhynchids. Because of this, the species was seen as a transitional form between long-snouted,

piscivorous A piscivore () is a carnivorous animal that eats primarily fish. The name ''piscivore'' is derived . Piscivore is equivalent to the Greek-derived word ichthyophage, both of which mean "fish eater". Fish were the diet of early tetrapod evoluti ...

metriorhynchids and

hypercarnivorous A hypercarnivore is an animal which has a diet that is more than 70% meat, either via active predation or by scavenging. The remaining non-meat diet may consist of non-animal foods such as fungi, fruits or other plant material. Some extant exampl ...

, short-snouted species of ''Dakosaurus''. ''T. coryphaeus'' reached in length, while ''T. carpenteri'' reached in length and weighed ; some specimens indicate an even larger body size. While ''Dakosaurus'' and ''Geosaurus'' have ziphodont dentition with teeth that are laterally compressed, ''Torvoneustes'' is unique in having a false-ziphodont dentition. The common ancestor of ''Dakosaurus'' and ''Geosaurus'' may also have had a ziphodont dentition, and as ''Torvoneustes'' is also a descendant of this common ancestor, it is possible that a ziphodont dentition was secondarily lost in the genus. However, it is also possible that ''Dakosaurus'' and ''Geosaurus'' acquired similar dentitions independently, and that ''Torvoneustes'' is not descended from a ziphodont ancestor. Fossil teeth of a similar form were also found in a stratum from the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

dating to late

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ...

References

Prehistoric pseudosuchian genera Prehistoric marine crocodylomorphs Kimmeridgian life Late Jurassic crocodylomorphs of Europe Jurassic England Fossils of England Late Jurassic crocodylomorphs of North America Jurassic Mexico Fossils of Mexico Fossil taxa described in 2008 Fossil taxa described in 2013 {{paleo-archosaur-stub