Pepesuchus
Encyclopedia
Pepesuchus is an extinct genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of carnivorous metasuchia
Metasuchia
Metasuchia is a major clade within the superorder Crocodylomorpha. It is split into two main groups, Notosuchia and Neosuchia. Notosuchia is an extinct group that contains primarily small-bodied Cretaceous taxa with heterodont dentitions. Neosuchia includes extant crocodylians and basal taxa such...

n from the late Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 period. It is a peirosaurid
Peirosauridae
Peirosauridae is a Gondwanan family of mesoeucrocodylians that lived during the Cretaceous period. It was a clade of terrestrial crocodyliforms that evolved a rather dog-like form, and were terrestrial carnivores. It was phylogenetically defined in 2004 as the most recent common ancestor of...

 which lived during the Campanian
Campanian
The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...

 and Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...

 stages of the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

 in what is now state of São Paulo, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

.

Etymology

Pepesuchus was named by Diogenes A. Campos, Gustavo R. Oliveira, Rodrigo G. Figueiredo, Douglas Riff, Sergio A.K. Azevedo, Luciana B. Carvalho and Alexander W.A. Kellner in 2011
2011 in paleontology
-Lobopods:-Arachnids:-Insects:-Newly named jawless vertebrates:-Newly named acanthodian:-Newly named cartilaginous fishes:-Newly named bony fishes:-Newly named lepospondyls:-Newly named temnospondyls:-Newly named lissamphibians:...

 and the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 is Pepesuchus deiseae. The generic name honours Professor José Martin Suárez (known by his colleagues as "Pepe"), and "suchus", from Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 meaning crocodile
Crocodile
A crocodile is any species belonging to the family Crocodylidae . The term can also be used more loosely to include all extant members of the order Crocodilia: i.e...

. The specific name honours the paleontologist Deise Dias Rêgo Henriques.

Description

Pepesuchus is known from the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

 MN
National Museum of Brazil
The National Museum of Brazil is a centenarian museum and research institution, located in the Quinta da Boa Vista park in the city of Rio de Janeiro, Brazil.-History:...

 7005-V, which consists of nearly complete skeleton
Skeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...

 and skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

, and from the paratype
Paratype
Paratype is a technical term used in the scientific naming of species and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany...

 MCT 1788-R, a nearly complete skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...

 and lower jaw likely from the same locality of the holotype. The specimens were recovered from the Presidente Prudente Formation of Bauru Group
Bauru Group
The Bauru Group is a geological formation in Brazil whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation. The Bauru Group was divided by Fernandes and Coimbra in four formations,namely Adamantina, Uberaba Araçatuba and...

, between the cities of Pirapozinho and Presidente Prudente.

The skull of Pepesuchus is roughly triangular when viewed from above and is covered in small pits. The jaws are lined with many small pointed teeth. Like other sebecia
Sebecia
Sebecia is an extinct clade of mesoeucrocodylian crocodyliforms that includes peirosaurids and sebecids. It was first constructed in 2007 to include Hamadasuchus, Peirosauridae, and Sebecus. It was initially considered to be the sister taxon of the clade Neosuchia, which includes living...

ns, Pepesuchus has ziphodont teeth that are laterally compressed and serrated. 17 teeth are present in each maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...

, the most of any sebecian after Stolokrosuchus
Stolokrosuchus
Stolokrosuchus is an extinct genus of neosuchian crocodylomorph that lived during the Early Cretaceous. Its fossils, including a skull with a long thin snout and bony knobs on the prefontals, have been found in Niger. Stolokrosuchus was described in 2000 by Hans Larsson and Boubacar Gado. The...

. There are also numerous dentary teeth in the lower jaw, with the foremost ones directed in a slight forward position. The snout of Pepesuchus is somewhat wider than those of other peirosaurids and has a slight upward curve.

Classification

Pepesuchus is united with the peirosaurids Peirosaurus
Peirosaurus
Peirosaurus is an extinct genus of peirosaurid crocodylomorph. It is the type genus of the family Peirosauridae. Fossils of the type species P. tormini, first described in 1955, have been found from the Marília Formation in Uberaba, Brazil and date back to the late Maastrichtian stage of the Late...

, Lomasuchus
Lomasuchus
Lomasuchus is an extinct genus of peirosaurid mesoeucrocodylian. Fossils have been found from the Bajo de la Carpa Formation of the Neuquén Group outcropping in Neuquén Province, Argentina...

, and Uberabasuchus
Uberabasuchus
Uberabasuchus is an extinct genus of crocodylomorph from the Late Cretaceous of Brazil.-Sources:* - original description of genus...

on the basis of several shared characteristics. Among these features are five premaxilla
Premaxilla
The incisive bone is the portion of the maxilla adjacent to the incisors. It is a pair of small cranial bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals....

ry teeth with the first two positioned close together and the oval-shaped cross-section of the jugal
Jugal
The jugal is a skull bone found in most reptiles, amphibians, and birds. In mammals, the jugal is often called the malar or Zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by species....

 bone that makes up the lower temporal bar underneath the eye sockets
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...

. Pepesuchus also has a ridge on the maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...

ry shelf of the palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...

, a feature it shares with all members of the larger clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 Sebecia
Sebecia
Sebecia is an extinct clade of mesoeucrocodylian crocodyliforms that includes peirosaurids and sebecids. It was first constructed in 2007 to include Hamadasuchus, Peirosauridae, and Sebecus. It was initially considered to be the sister taxon of the clade Neosuchia, which includes living...

 (which includes peirosaurids and the related family Sebecidae
Sebecidae
Sebecidae is an extinct family of prehistoric crocodylomorphs. They lived mostly in Argentina.This group included many medium and large - sized genera, from Sebecus to a giant indeterminate unnamed species from the Miocene.-Phylogeny:...

).
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