Notosuchia is a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

of primarily

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

mesoeucrocodylia Mesoeucrocodylia is the clade that includes Eusuchia and crocodyliforms formerly placed in the paraphyletic group Mesosuchia. The group appeared during the Early Jurassic, and continues to the present day. Diagnosis It was long known that Me ...

crocodylomorph Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. Extinct crocodylomorphs were considerably mor ...

s that lived during the

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

and

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

. Some

phylogenies A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA. In o ...

recover

Sebecosuchia Sebecosuchia (meaning "Sobek crocodiles") is an extinct group of mesoeucrocodylian crocodyliforms that includes the families Sebecidae and Baurusuchidae. The group was long thought to have first appeared in the Late Cretaceous with the baurusu ...

as a

within Notosuchia, others as a

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

(see

below Below may refer to: *Earth *Ground (disambiguation) *Soil *Floor * Bottom (disambiguation) *Less than *Temperatures below freezing *Hell or underworld People with the surname * Ernst von Below (1863–1955), German World War I general * Fred Belo ...

); if Sebecosuchia is included within Notosuchia its existence is pushed into the

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d ...

, about 7 to 4.5 million years ago.

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s have been found from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

, and

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

. Notosuchia was a clade of terrestrial crocodilians that evolved a range of feeding behaviours, including herbivory ('' Chimaerasuchus''), omnivory ('' Simosuchus''), and terrestrial hypercarnivory (''

Baurusuchus ''Baurusuchus'' is an extinct genus of baurusuchid mesoeucrocodylian, which lived in Brazil from 90 to 83.5 million years ago, in the Late Cretaceous period. It was a terrestrial predator, estimated to reach up to in weight. ''Baurusuchus' ...

''). It included many members with highly derived traits unusual for crocodylomorphs, including mammal-like teeth, flexible bands of shield-like body armor similar to those of

armadillo Armadillos () are New World placental mammals in the order (biology), order Cingulata. They form part of the superorder Xenarthra, along with the anteaters and sloths. 21 extant species of armadillo have been described, some of which are dis ...

s ('' Armadillosuchus''), and possibly fleshy cheeks and pig-like snouts (''

Notosuchus ''Notosuchus'' (; 'southern crocodile') is an extinct genus of South American notosuchian crocodyliforms. It was terrestrial, living approximately 85 million years ago in the Santonian stage of the Late Cretaceous. Description ''Notosuchus'' ...

''). The clade was first named in 1971 by Zulma Gasparini and has since undergone many phylogenetic revisions.

Description

Notosuchians were generally small, with slender bodies and erect limbs. The most distinctive characteristics are usually seen in the skull. Notosuchian skulls are generally short and deep. While most are relatively narrow, some are very broad. '' Simosuchus'' has a broadened skull and jaw that resembles a

pug The Pug is a breed of dog with the physically distinctive features of a wrinkly, short-muzzled face, and curled tail. An ancient breed, with roots dating back to 400 B.C., they have a fine, glossy coat that comes in a variety of colors, most ...

, while ''

Anatosuchus ''Anatosuchus'' ("duck crocodile", the name from the Latin ''anas'' ("duck") and the Greek ''souchos'' ("crocodile"), for the broad, duck-like snout) is an extinct genus of notosuchian crocodyliforms discovered in Gadoufaoua, Niger, and described ...

'' has a broad, flat snout like that of a

duck Duck is the common name for numerous species of waterfowl in the family (biology), family Anatidae. Ducks are generally smaller and shorter-necked than swans and goose, geese, which are members of the same family. Divided among several subfam ...

. The teeth vary greatly between different genera. Many have

heterodont In anatomy, a heterodont (from Greek, meaning 'different teeth') is an animal which possesses more than a single tooth morphology. Human dentition is heterodont and diphyodont as an example. In vertebrates, heterodont pertains to animals wher ...

dentitions that vary in shape across the jaw. Often, there are large canine-like teeth protruding from the front of the mouth and broader molar-like teeth in the back. Some genera, such as '' Yacarerani'' and ''

Pakasuchus ''Pakasuchus'' is a genus of notosuchian crocodyliform distinguished by its unusual mammal-like appearance, including mammal-like teeth that would have given the animal the ability to chew. It also had long, slender legs and a doglike nose. Fossi ...

'', have extremely mammal-like teeth. Their molars are complex and

multicuspid The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth ...

, and are able to occlude or fit with one another. Some forms such as ''

Malawisuchus ''Malawisuchus'' (meaning "Malawi crocodile") is an extinct genus of notosuchian mesoeucrocodylian from the Early Cretaceous Dinosaur Beds of Malawi. It was described in 1997 by Elizabeth Gomani as a member of the family Notosuchidae. The type ...

'' had jaw joints that enabled them to move the jaw back and forth in a shearing motion rather than just up and down. A derived group of notosuchians, the baurusuchids differ considerably from other forms. They are very large in comparison to other notosuchians and are exclusively carnivorous. Baurusuchids have deep skulls and prominent canine-like teeth. Recent research found ''

Araripesuchus wegeneri ''Araripesuchus'' is a genus of extinct crocodyliform that existed during the Cretaceous period of the late Mesozoic era some 125 to 66 million years ago. ''Araripesuchus'' is generally considered to be a notosuchian (belonging to the clade Mesoe ...

'', '' Armadillosuchus arrudai'', ''

'', '' Iberosuchus macrodon'', and '' Stratiotosuchus maxhechti'' were ectothermic organisms

Classification

Taxonomy

Genera

The evolutionary interrelationships of Notosuchia are in flux, but the following genera are generally considered notosuchians:

Phylogeny

The clade Notosuchia has undergone many recent phylogenetic revisions. In 2000, Notosuchia was proposed to be one of two groups within the clade

Ziphosuchia Ziphosuchia is a clade of mesoeucrocodylian crocodyliforms that includes notosuchians and sebecosuchians. Systematics First constructed in 2000, it was considered to include '' Notosuchus'', '' Libycosuchus'', and Sebecosuchia. In a 2004 phylog ...

, the other being

, which included deep snouted forms such as baurusuchids and sebecids. The definition of Notosuchia by Sereno et al. (2001) is similar to that of Ziphosuchia as it includes within it Sebecosuchia. Pol (2003) also includes Sebecosuchia within Notosuchia. More recently, a phylogenetic analysis by Larsson and Sues (2007) resulted in the naming of a new clade,

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 ...

, to include sebecids and

peirosaurids Peirosauridae is a Gondwanan family of mesoeucrocodylians that lived during the Cretaceous period (geology), period. It was a clade of terrestrial crocodyliforms that evolved a rather dog-like skull, and were terrestrial carnivores. It was phylog ...

. Baurusuchidae was considered to be polyphyletic in this study, with '' Pabwehshi'' being a basal member of Sebecia and ''

'' being the sister taxon to the clade containing

Neosuchia Neosuchia is a clade within Mesoeucrocodylia that includes all modern extant crocodilians and their closest fossil relatives. It is defined as the most inclusive clade containing all Crocodylomorpha, crocodylomorphs more closely related to ''Croc ...

and Sebecia. Thus, Sebecosuchia was no longer within Notosuchia and not considered to be a true clade, while Notosuchia was found to be a basal clade of Metasuchia. 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 ...

simplified after the most comprehensive analysis of notosuchians as of 2014, presented by Pol ''et al.'' in 2014. It is based mainly on the data matrix published by Pol ''et al.'' (2012) which is itself a modified version of previous analyses. Thirty-one additional characters were added from other comprehensive analyses of notosuchians, e.g. Turner and Sertich (2010), Andrade ''et al.'' (2011), Montefeltro ''et al.'' (2011), Larsson and Sues (2007), and Novas ''et al.'' (2009), and 34 characters were noval, resulting in a matrix that includes 109

crocodyliform Crocodyliformes is a clade of Crurotarsi, crurotarsan archosaurs, the group often traditionally referred to as "crocodilians". They are the first members of Crocodylomorpha to possess many of the features that define later relatives. They are the ...

s and outgroup taxa which are scored based on 412 morphological traits. This cladogram represents the results of the most comprehensive analysis of notosuchian relationships to date, performed in the description of '' Antaeusuchus taouzensis'' by Nicholl ''et al.'' 2021. It is largely based on the matrix from the above Pol ''et al.'' 2014 study, but also adding character scores from Leardi ''et al.'' 2015, Fiorelli ''et al.'' 2016, Leardi ''et al.'' 2018, and Martinez ''et al.'' 2018. The final matrix consisted of 121 taxa scored for 443 morphological traits.

Subclades

There is uncertainty on the precise interrelationships between different notosuchian families. This is a summary on the phylogenetic definitions of higher-level notosuchian clades from Leardi ''et al.'' 2024.

References

{{Taxonbar, from=Q134397 Early Cretaceous crocodylomorphs Terrestrial crocodylomorphs Bathonian first appearances Maastrichtian extinctions Miocene extinctions Taxa named by Zulma Brandoni de Gasparini