Notosuchia is a suborder of primarily

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final sta ...

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 Mes ...

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. During Mesozoic and early Cenozoic times, cro ...

s that lived during the

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

and

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

. Some

phylogenies A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

recover

Sebecosuchia Sebecosuchia 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 baurusuchids and become extinct in th ...

as a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...

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 Below ...

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

Middle Miocene The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0.05 Ma to 11.608 ± 0.005 Ma (million ...

, about 11 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 preserved ...

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 relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sou ...

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

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

, and

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

. Notosuchia was a

of terrestrial crocodilians that evolved a range of feeding behaviours, including herbivory ('' Chimaerasuchus''), omnivory (''

Simosuchus ''Simosuchus'' (meaning "pug-nosed crocodile" in Greek, referring to the animal's blunt snout) is an extinct genus of notosuchian crocodylomorphs from the Late Cretaceous of Madagascar. It is named for its unusually short skull. Fully grown indi ...

''), and terrestrial hypercarnivory ('' 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 (meaning "little armored ones" in Spanish) are New World placental mammals in the order Cingulata. The Chlamyphoridae and Dasypodidae are the only surviving families in the order, which is part of the superorder Xenarthra, alo ...

s ('' Armadillosuchus''), and possibly fleshy cheeks and pig-like snouts ('' Notosuchus''). The suborder was first named in 1971 by

Zulma Gasparini Zulma Nélida Brandoni de Gasparini (born 15 May 1944) is an Argentinian paleontologist and zoologist. She is known for discovering the fossils of the dinosaur ''Gasparinisaura'', which was named after her. Work Born in the city of La Plata, ...

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. ''

'' has a broadened skull and jaw that resembles a pug, while '' Anatosuchus'' has a broad, flat snout like that of a

duck Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form ...

. 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. In vertebrates, heterodont pertains to animals where teeth are differentiated into different forms. For exampl ...

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'', have extremely mammal-like teeth. Their molars are complex and multicuspid, and are able to occlude or fit with one another. Some forms such as '' Malawisuchus'' 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

baurusuchid Baurusuchidae is a Gondwanan family of mesoeucrocodylians that lived during the Late Cretaceous. It is a group of terrestrial hypercarnivorous crocodilians from South America (Argentina and Brazil) and possibly Pakistan. Baurusuchidae has been, ...

s 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.

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, the other being

, which included deep snouted forms such as

s and

sebecid Sebecidae is an extinct family of prehistoric terrestrial sebecosuchian crocodylomorphs. The oldest known member of the group is ''Ogresuchus furatus'' known from the Upper Cretaceous (Maastrichtian) Tremp Formation (Spain). Sebecids were divers ...

s. 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, to include sebecids and

peirosaurids 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 ...

. Baurusuchidae was considered to be polyphyletic in this study, with '' Pabwehshi'' being a basal member of Sebecia and '' Baurusuchus'' 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 crocodylomorphs more closely related to ''Crocodylus niloticu ...

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 ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

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 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 only pseu ...

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.

References

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