''Caryonosuchus'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of sphagesaurid

notosuchian Notosuchia is a clade of primarily Gondwanan mesoeucrocodylian Crocodylomorpha, crocodylomorphs that lived during the Jurassic and Cretaceous. Some phylogeny, phylogenies recover Sebecosuchia as a clade within Notosuchia, others as a sister group ...

known from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

São Paulo State SAO or Sao may refer to: Places * Sao civilisation, in Middle Africa from 6th century BC to 16th century AD * Sao, a town in Boussé Department, Burkina Faso * Serb Autonomous Regions (''Srpska autonomna oblast'', SAO), during the breakup of ...

, southeastern

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

Discovery

''Caryonosuchus'' is known only from the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen DGM 1411-R, a nearly complete anterior portion of the

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

and

lower jaw In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

which housed at the Earth Science Museum of the Departamento Nacional da Produção Mineral. A cast is housed at the Departamento de Geologia, Universidade Federal do Rio de Janeiro. It was found near

Presidente Prudente Presidente Prudente is a Municipalities of Brazil, Brazilian municipality located in the Interior of São Paulo, interior of São Paulo (state), São Paulo, approximately 558 kilometers from the state capital, São Paulo. According to the 2024 e ...

City of southwest

. It was collected from the

Adamantina Formation The Adamantina Formation is a geological Formation (geology), formation in the Bauru Basin of western São Paulo (state), São Paulo state in southeastern Brazil. Its strata date back to the Late Cretaceous epoch of the Cretaceous, Cretaceous Per ...

of the

Bauru Basin The Bauru Group is a geological group of the Bauru Sub-basin, Paraná Basin in Minas Gerais, São Paulo, General Salgado, Itapecuru-Mirim, Mato Grosso, Brazil whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils t ...

, which dates to the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

and

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

stages of the Late Cretaceous. DGM 1411-R was briefly mentioned before the description of ''Caryonosuchus''. For example, Kellner & Campos (1999) tentatively assigned it to '' Sphagesaurus'' sp.,A. W. A. Kellner and D. d. A. Campos. (1999). Vertebrate paleontology in Brazil — a review. ''Episodes'' 22(3):238-251 however newly described

cranial Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Thi ...

sphagesaurid remains may suggest that the

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

of the family, '' Sphagesaurus huenei'', is a

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

. Thus, DGM 1411-R is regarded as a new genus and species.

Description

''Caryonosuchus'' is characterized by a unique combination of characters, including three

autapomorphies In phylogenetics, an autapomorphy is a distinctive feature, known as a derived trait, that is unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa, not even those most closely related to ...

(unique characteristics) such as a

rostrum Rostrum may refer to: * Any kind of a platform for a speaker: **dais **pulpit ** podium * Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects * Rostrum (ship), a form of bow on naval ...

with horn-like tubercles on the

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

and on the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

. ''Caryonosuchus'' also has autapomorphic rough ornamentation with grooves and bony ridges on its rostrum. DGM 1411-R was found to be an advanced sphagesaurid in a

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis published by de Andrade ''et al.'' (2011). The following

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

shows the position of ''Caryonosuchus'' among other sphagesaurids sensu this study.

Etymology

''Caryonosuchus'' was first named by Alexander W. A. Kellner, Diogenes A. Campos, Douglas Riff and Marco Brandalise de Andrade in

2011 The year marked the start of a Arab Spring, series of protests and revolutions throughout the Arab world advocating for democracy, reform, and economic recovery, later leading to the depositions of world leaders in Tunisia, Egypt, and Yemen ...

and the

is ''Caryonosuchus pricei''. The generic name is derived from

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

''káryon'' meaning "kernel" or "protuberance" and ''souchos'' meaning "crocodile". The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

honors

Llewellyn Ivor Price Llewellyn Ivor Price (October 9, 1905 – June 9, 1980) was one of the first Brazilian paleontologists. His work contributed not only to the development of Brazilian but also to global paleontology. He collected ''Staurikosaurus'' in 1936, th ...

, a palaeontologist who described and named the genus '' Sphagesaurus'' and described the holotype of ''Caryonosuchus'' in an unpublished manuscript.

References

{{Taxonbar, from=Q5047729 Late Cretaceous crocodylomorphs of South America Terrestrial crocodylomorphs Fossil taxa described in 2011 Sphagesauridae Adamantina Formation Prehistoric pseudosuchian genera