Neosuchia is a clade within

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 M ...

that includes all modern extant

crocodilia Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period ( Cenomanian stage) and are the closest livi ...

ns and their closest fossil relatives. It is defined as the most inclusive clade containing all

crocodylomorphs 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, cr ...

more closely related to ''

Crocodylus niloticus ''Crocodylus'' is a genus of true crocodiles in the family Crocodylidae. Taxonomy The generic name, ''Crocodylus'', was proposed by Josephus Nicolaus Laurenti in 1768. ''Crocodylus'' contains 13–14 extant (living) species and 5 extinct sp ...

'' (the

Nile Crocodile The Nile crocodile (''Crocodylus niloticus'') is a large crocodilian native to freshwater habitats in Africa, where it is present in 26 countries. It is widely distributed throughout sub-Saharan Africa, occurring mostly in the central, eastern ...

) than to '' Notosuchus terrestris''. Members of Neosuchia generally share a crocodilian-like bodyform adapted to freshwater aquatic life, as opposed to the terrestrial habits of more basal crocodylomorph groups. The earliest neosuchian is suggested to be the

Early Jurassic The Early Jurassic Epoch (in chronostratigraphy corresponding to the Lower Jurassic Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma ...

Calsoyasuchus ''Calsoyasuchus'' (meaning " r. KyrilCalsoyas' crocodile") is a genus of crocodylomorph that lived in the Early Jurassic. Its fossilized remains were found in the Sinemurian-Pliensbachian-age Kayenta Formation on Navajo Nation land in Coconino ...

'', which lived during the

Sinemurian In the geologic timescale, the Sinemurian is an age and stage in the Early or Lower Jurassic Epoch or Series. It spans the time between 199.3 ± 2 Ma and 190.8 ± 1.5 Ma (million years ago). The Sinemurian is preceded by the Hettangian an ...

and

Pliensbachian The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 190.8 ± 1.5 Ma and 182.7 ± 1.5 Ma (million years ago). The ...

stages in North America. It is often identified as a member of

Goniopholididae Goniopholididae is an extinct family of moderate-sized semi-aquatic neosuchian crocodyliformes. Their bodyplan and morphology are convergent on living crocodilians. They lived across Laurasia (Asia, Europe and North America) between the Middle J ...

, though this is disputed, and the taxon may lie outside Neosuchia, which places the earliest records of the group in the Middle Jurassic.

Characteristics

A tooth notch between the

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates 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 ...

and

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 mammal has ...

is a basal characteristic of the Neosuchia, although it is lost in some more

derived Derive may refer to: * Derive (computer algebra system), a commercial system made by Texas Instruments * ''Dérive'' (magazine), an Austrian science magazine on urbanism *Dérive, a psychogeographical concept See also * *Derivation (disambiguatio ...

forms, most notably alligatorids.

Classification

* Basal Neosuchia ** Genus ''

Burkesuchus ''Burkesuchus'' (meaning "Coleman Burke's crocodile") is an extinct genus of basal neosuchians from the Upper Jurassic (Tithonian)-aged Toqui Formation of southern Chile. The genus is currently represented by a single species ''B. mallingrandens ...

''? ** Genus ''

Deltasuchus ''Deltasuchus'' ("delta crocodile") is a genus of neosuchian crocodyliform from the Late Cretaceous of Texas, specifically in the Woodbine Formation, which was a part of the Appalachian continent during the Cretaceous. It is known from one speci ...

'' ** Genus ''

Khoratosuchus ''Khoratosuchus'' is an extinct genus of neosuchian crocodylomorph which existed in northeast Thailand during the early Cretaceous period. Its type species is ''Khoratosuchus jintasakuli''. ''Khoratosuchus'' is the youngest and most advanced Me ...

'' ** Genus ''

Lisboasaurus ''Lisboasaurus'' is a small (400 mm length) genus of Mesozoic crocodylomorph that lived in fresh water. It is known from fossilized tooth and jaw fragments of Late Jurassic and Early Cretaceous age. Two species have been described. In the pa ...

'' ** Genus '' Paluxysuchus'' ** Genus ''

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 prefrontal, have been found in Niger. ''Stolokrosuchus'' w ...

'' ** Genus '' Wahasuchus''? ** Family Susisuchidae ** Clade

Coelognathosuchia Coelognathosuchia is an extinct clade of neosuchian crocodyliforms that includes all taxa more closely related to the family Pholidosauridae than to ''Bernissartia fagesii'' or Eusuchia. Martin ''et al.'' (2014) named the clade after finding g ...

*** Family

*** ?Family

Pholidosauridae Pholidosauridae is an extinct family of aquatic neosuchian mesoeucrocodylian crocodylomorphs. Fossils have been found in Europe (Denmark, England, France, Germany, Spain and Sweden), Africa (Algeria, Niger, Mali, Morocco and Tunisia), North Amer ...

** Suborder

Tethysuchia Tethysuchia is an extinct clade of neosuchian mesoeucrocodylian crocodylomorphs from the late Middle Jurassic ( Bathonian stage) to the Early Eocene ( Ypresian stage) of Asia, Europe, North America and South America. It was named by the Fren ...

*** Family Elosuchidae *** Family

Dyrosauridae Dyrosauridae is a family (biology), family of extinct neosuchian crocodyliforms that lived from the Late Cretaceous (Maastrichtian) to the Eocene. Dyrosaurid fossils are globally distributed, having been found in Africa, Asia, Europe, North Amer ...

*** Family

** Family

Stomatosuchidae Stomatosuchidae is an extinct family of neosuchian crocodylomorphs. It is defined as the most inclusive clade containing ''Stomatosuchus inermis'' but not '' Notosuchus terrestris'', ''Simosuchus clarki'', '' Araripesuchus gomesii'', ''Baurusuc ...

** Family

Bernissartiidae Bernissartiidae is an extinct family of neosuchian crocodyliformes known from the Early Cretaceous. Bernissartiid fossils have been reported from Belgium, France, Spain, England, Tunisia and the United States. It currently contains two genera, '' ...

** Genus ''

Gilchristosuchus ''Gilchristosuchus'' (meaning "Gilchrist type_specimen.html" ;"title="he owners of the ranch where the type specimen">he owners of the ranch where the type specimen was foundcrocodile") is an extinct genus of neosuchian crocodyliform.Crocodylifo ...

'' ** Suborder

Eusuchia Eusuchia is a clade of crocodylomorphs that first appeared in the Early Cretaceous with '' Hylaeochampsa''. Along with Dyrosauridae and Sebecosuchia, they were the only crocodyliformes who survived the K-T extinction. Since the other two clades ...

Phylogeny

Below is a

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 ...

showing the

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

relationships of neosuchians from Buscalioni ''et al.'', 2011: In 2012, paleontologists Mario Bronzati, Felipe Chinaglia Montefeltro, and Max C. Langer conducted a broad phylogenetic analysis to produce

supertree A supertree is a single phylogenetic tree assembled from a combination of smaller phylogenetic trees, which may have been assembled using different datasets (e.g. morphological and molecular) or a different selection of taxa. Supertree algorithms c ...

s of Crocodyliformes, including 184 species. The most parsimonious trees were highly resolved, meaning the phylogenetic relationships found in the analysis were highly likely. Below is a consensus tree from the study:

References

External links

Neosuchia
in the

Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Paleo ...

{{Taxonbar, from=Q3042061 Jurassic crocodylomorphs Cretaceous crocodylomorphs Paleogene crocodylomorphs Neogene crocodylomorphs Extant Early Jurassic first appearances