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Prehistoric Crocodiles
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http://news.nationalgeographic.com/2016/...eontology/
The biggest sea-dwelling crocodile ever found has turned up in the Tunisian desert. The whopper of a prehistoric predator grew to over 30 feet long (nearly ten meters) and weighed three tons. 
A New 13 Million Year Old Gavialoid Crocodylian from Proto-Amazonian Mega-Wetlands Reveals Parallel Evolutionary Trends in Skull Shape Linked to Longirostry
Gryposuchus pachakamue Salas-Gismondi et al., 2016  *This image is copyright of its original author Fig 2. Gryposuchus pachakamue sp. nov. Photograph and schematic drawing of the skull (holotype, MUSM 1981) in dorsal (A), ventral (B), and lateral © view. (D) Photograph of the right mandible (MUSM 987) and schematic drawing in dorsal view. Details of the skull (E,F). (E) MUSM 900 in lateral view. (F) MUSM 1681 in occipital view. Abstract: "Gavialoid crocodylians are the archetypal longirostrine archosaurs and, as such, understanding their patterns of evolution is fundamental to recognizing cranial rearrangements and reconstructing adaptive pathways associated with elongation of the rostrum (longirostry). The living Indian gharial Gavialis gangeticus is the sole survivor of the group, thus providing unique evidence on the distinctive biology of its fossil kin. Yet phylogenetic relationships and evolutionary ecology spanning ~70 million-years of longirostrine crocodylian diversification remain unclear. Analysis of cranial anatomy of a new proto-Amazonian gavialoid, Gryposuchus pachakamue sp. nov., from the Miocene lakes and swamps of the Pebas Mega-Wetland System reveals that acquisition of both widely separated and protruding eyes (telescoped orbits) and riverine ecology within South American and Indian gavialoids is the result of parallel evolution. Phylogenetic and morphometric analyses show that, in association with longirostry, circumorbital bone configuration can evolve rapidly for coping with trends in environmental conditions and may reflect shifts in feeding strategy. Our results support a long-term radiation of the South American forms, with taxa occupying either extreme of the gavialoid morphospace showing preferences for coastal marine versus fluvial environments. The early biogeographic history of South American gavialoids was strongly linked to the northward drainage system connecting proto-Amazonian wetlands to the Caribbean region." Other articles related: The Secrets of the 13 Million-Year-Old Crocodile
http://www.eartharchives.org/articles/mo...iscovered/
Around 120 million years ago, there lived a monstrous marine crocodile relative named Machimosaurus rex. Its massive jaws could crush turtle shells and it terrorized the warm seas that covered what are now the deserts of Tunisia.
New Spanish Late Cretaceous eusuchian reveals the synchronic and sympatric presence of two allodaposuchids
Agaresuchus fontisensis Narváez, Brochu, Escaso, Pérez-García, & Ortega, 2016  *This image is copyright of its original author Fig. 2. Skull HUE-02502, holotype of Agaresuchus fontisensis gen. et sp. nov., from the upper Campanianelower Maastrichtian site of Lo Hueco (Cuenca, Spain). (A, B) Dorsal views. (C, D) Ventral views. A and C, photographs of the specimen. B and D, interpretative drawings. Sutures are figured with plain lines. The dashed lines represent tentatively reconstructed sutures. The lined areas represent broken bones. Abstract: "The recently described clade Allodaposuchidae includes European eusuchian crocodyliforms restricted to the Late Cretaceous (Campanian and Maastrichtian). A new allodaposuchid crocodyliform is here described based on two specimens from the upper Campanian–lower Maastrichtian fossil site of Lo Hueco (Cuenca, Spain). This new taxon, Agaresuchus fontisensis gen. et sp. nov., is described by two complete skulls and a lower jaw associated with one of them. This new species can be distinguished unambiguously from Lohuecosuchus megadontos, the other allodaposuchid known from the same fossil site. The presence of two allodaposuchid crocodyliforms in Lo Hueco allows the recognition of the synchronic and sympatric existence of two representatives of this clade for the first time. The new genus Agaresuchus, comprises a previously described Iberian allodaposuchid species, “Allodaposuchus” subjuniperus, as Agaresuchus subjuniperus, new combination." Full Article Other articles related: Este miércoles se presenta el Agaresuchus fontisensis, nueva especie de cocodrilo hallada en Lo Hueco Hallan una especie que podría pertenecer al grupo antecesor de los cocodrilos actuales en Cuenca
http://www.eartharchives.org/articles/th...russaurus/
Purussaurus is one of the biggest, yet most poorly understood of all massive crocodilians. For a while not much was known about it besides its size and strength. Recently though, new scientific research is uncovering its most lethal secret: Its monstrous seven-ton bite.
Neural and endocranial anatomy of Triassic phytosaurian reptiles and convergence with fossil and modern crocodylians Lautenschlager & Butler, 2016
 *This image is copyright of its original author Figure 2: Endocranial anatomy of Parasuchus angustifrons (BSPG 1931 X 502). Endocast of brain and endosseous labyrinth in (A) left lateral and (B) dorsal view. Endocast in situ in © left lateral and (D) dorsal view with bone rendered semi-transparent.  *This image is copyright of its original author Figure 3: Endocranial anatomy of Ebrachosuchus neukami (BSPG 1931 X 501). Endocast of brain and endosseous labyrinth in (A) left lateral and (B) dorsal view. Endocast in situ in © left lateral and (D) dorsal view with bone rendered semi-transparent. Abstract: "Phytosaurs are a clade of large, carnivorous pseudosuchian archosaurs from the Late Triassic with a near cosmopolitan distribution. Their superficial resemblance to longirostrine (long-snouted) crocodylians, such as gharials, has often been used in the past to infer ecological and behavioural convergence between the two groups. Although more than thirty species of phytosaur are currently recognised, little is known about the endocranial anatomy of this clade. Here, we describe the endocranial anatomy (including the brain, inner ear, neurovascular structures and sinus systems) of the two non-mystriosuchine phytosaurs Parasuchus angustifrons (=“Paleorhinus angustifrons”) and Ebrachosuchus neukami from the Late Triassic of Germany based on digital reconstructions. Results show that the endocasts of both taxa are very similar to each other in their rostrocaudally elongate morphology, with long olfactory tracts, weakly demarcated cerebral regions and dorsoventrally short endosseous labyrinths. In addition, several sinuses, including large antorbital sinuses and prominent dural venous sinuses, were reconstructed. Comparisons with the endocranial anatomy of derived phytosaurs indicate that Phytosauria is united by the presence of elongate olfactory tracts and longitudinally arranged brain architecture—characters which are also shared with Crocodyliformes. However, a substantial morphological variability is observed in the cephalic and pontine flexure and the presence of a pineal organ across the different phytosaur species. These results suggest that the endocranial anatomy in Phytosauria generally follows a plesiomorphic pattern, with moderate variation within the clade likely resulting from divergent sensory and behavioural adaptations." Other articles related: Brain anatomy convergence between crocodylians and their epic carnivorous cousins, the phytosaurs 
Deinosuchus
 *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author Deinosuchus. Because no complete individual has yet been described, we are forced to make extrapolations of their possible total lengths from the parts we know from several complete jaws. A estimated total length of 11 mt based on a estimate of 1,8 mt jaw from texas and a estimated weight of 6 tons. (Book King of the Crocodylians David R. Schwimer)
Razanandrongobe sakalavae, a gigantic mesoeucrocodylian from the Middle Jurassic of Madagascar, is the oldest known notosuchian Dal Sasso et al., 2017
Razanandrongobe sakalavae Manganuco, Dal Sasso & Pasini, 2017  *This image is copyright of its original author A paleoartistic restoration of Razanandrongobe sakalavae scavenging on a sauropod carcass in the Middle Jurassic of Madagascar. Unlike extant crocodilians, this terrestrial predator had a deep skull and walked on erect limbs. Credit: Fabio Manucci Abstract: "Razanandrongobe sakalavae Maganuco, Dal Sasso & Pasini, 2006 is a large predatory archosaur from the Middle Jurassic (Bathonian) of the Mahajanga Basin, NW Madagascar. It was diagnosed on the basis of teeth and a fragmentary maxilla, but its affinities were uncertain. Here we describe new cranial remains (above all, an almost complete right premaxilla and a caudally incomplete left dentary) that greatly improve our knowledge on this enigmatic species and reveal its anatomy to be crocodylomorph. The right premaxilla indicates that the rostrum was deep, wide, and not pointed; it bears five teeth that are sub-vertical and just slightly curved lingually; the mesial teeth are U-shaped in cross-section and have serrated carinae on the lingual side; the aperturae nasi osseae (external bony nares) are confluent and face rostrally; and there is no lateral groove at the premaxillomaxillary suture for reception of a hypertrophied lower caniniform tooth. The preserved portion of the left dentary has an edentulous tip and bears eight large mandibular teeth of which the mesial (1–3) are the largest, but none is a hypertrophied caniniform tooth; the mandibular (dentary) symphysis extends caudally to the level of the third tooth; the splenial is not preserved, but its sutural marks on the dentary indicate that it contributed to the mandibular symphysis for at least 20% of the symphyseal length in dorsal aspect. On the basis of this new data, some previously uncertain features of the holotype maxilla—such as the margin of the suborbital fenestra, the contact surfaces for the palatine, the ectopterygoid, and the jugal—are now apparent. Testing of the phylogenetic position of the species within Crocodylomorpha indicates that R. sakalavae is a mesoeucrocodylian. It also represents one of the earliest events of exacerbated increase in body size along the evolutionary history of the group. In addition, it is by far the oldest notosuchian. A cranial reconstruction of this gigantic predator is also attempted here. The very robust jaw bones of R. sakalavae, coupled with its peculiar dentition, strongly suggest a diet that included hard tissue such as bone and tendon." Other articles related: Gigantic crocodile with T. rex teeth was a top land predator of the Jurassic in Madagascar
Gryposuchus croizate
A species described in 2008, G. croizati, found from the upper Miocene Urumaco Formation in northwestern Venezuela, can be distinguished from other species of Gryposuchus on the basis of a reduced number of maxillary teeth, a slender parietal interfenestral bar, and widely separated and reduced palatine fenestrae, among other things. Based on measurements of the orbital cranial skeleton, the length of the animal has been estimated at around 10.15 m in length, with a total mass of about 1745 kg. Measuring the entire length of the skull from the end of the rostrum to the supraoccipital would result in a much larger size estimate, up to three times as great. However, because there is considerable variation seen in rostral proportions among crocodilians, the latter measurements are probably not an accurate way of estimating body mass and length. Despite this, the species is still one of the largest crocodilians known to have existed, and it may indeed have been the largest gavialoid to have ever existed if a recent revision in the estimated size of the large tomistomine Rhamphosuchus is correct (the genus was once considered to be 15 m in length; the new estimate puts it at approximately 10 m). Picture and Artwork credits to Jorge Gonzalez  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author
Sarcosuchus imperator: is an extinct genus of crocodyliform and distant relative of living crocodylians that lived 112 million years ago. It dates from the early Cretaceous Period of what is now Africa and South America and is one of the largest crocodile-like reptiles that ever lived. It was almost twice as long as the modern saltwater crocodile and weighed up to 8 tonnes.A common method to estimate the size of crocodiles and crocodile-like reptiles is the use of the length of the skull measured in the midline from the tip of the snout to the back of the skull table, since in living crocodilians there is a strong correlation between skull length and total body length in subadult and adult individuals irrespective of their sex, this method is preferred for Sarcosuchus due to the absence of a complete enough skeleton.
Two regression equations were used to estimate the size of S. imperator, they were created based on measurements gathered from 17 captive gharial individuals from northern India and from 28 wild saltwater crocodile individuals from northern Australia, both datasets supplemented by available measurements of individuals over 1.5 m (4.9 ft) in length found in the literature.The largest known skull of S. imperator (the type specimen) is 1.6 m (5.2 ft) long, and it was estimated that the individual it belonged to had a total body length of 11.65 m (38.2 ft), its snout-vent length of 5.7 m (19 ft) was estimated using linear equations for the saltwater crocodile and in turn this measurement was used to estimate its body weight at 8 tonnes (8.8 short tons). This shows that Sarcosuchus was able to reach a maximum body size not only greater than previously estimated but also greater than that of the Miocene Rhamphosuchus, only the Late Cretaceous Deinosuchus and the Miocene Purussaurus may have achieved a comparable maximum body size.  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author
A new Mourasuchus (Alligatoroidea, Caimaninae) from the late Miocene of Venezuela, the phylogeny of Caimaninae and considerations on the feeding habits of Mourasuchus
Mourasuchus pattersoni Cidade et al., 2017  *This image is copyright of its original author Figure 2: Skull of Mourasuchus pattersoni sp. nov. (MCNC-PAL-110-72V, holotype) in dorsal view (A) with schematic drawing (B). In dark grey, the areas covered by plaster. Abbreviations: if, incisive foramen; ift, infratemporal fenestra; j, jugal; l, lacrimal; m, maxilla; n, nasal; of, occlusal fossa; or, orbit; pf, prefrontal; pm, premaxilla; pt: pterygoid; q, quadrate; qj, quadratojugal. Scale bar equals 20 cm. Abstract: "Mourasuchus (Alligatoroidea, Caimaninae) is one of the most peculiar crocodyliforms due to the skull morphology consisting of a long, wide, dorsoventrally flat rostrum with long, slender mandibular rami. Despite these peculiarities, the systematics, phylogeny and feeding habits of this taxon have not been properly studied. In this paper, we describe a new species of the genus, Mourasuchus pattersoni sp. nov., from the late Miocene of the Urumaco Formation of Venezuela. The new species differs from the other Mourasuchus species in having a lateromedially wide, dorsoventrally high jugal bone and a circular incisive foramen, which both represent autapomorphies of the new taxon. Phylogenetically, M. pattersoni sp. nov. is more closely related to M. amazonensis and the specimen UFAC-1424 (formely attributed to M. nativus) than to M. arendsi or M. atopus, whilst Mourasuchus is recovered once more as a monophyletic group. Furthermore, the cladistic analysis performed in this contribution offers a new phylogenetic assessment of Caimaninae, including many taxa described recently for the group. In this study, we also discuss the crocodylian diversity of the Urumaco Formation as well as how paleoenvironment may have contributed toward its evolution. In addition, we provide a discussion of the potential feeding habits of Mourasuchus. In this contribution, Mourasuchus is regarded as a taxon that likely preferred to prey on small animals. The unusual skull morphology of this group may have evolved to cover a large area with the rostrum, allowing for a more efficient prey capture, while the prey may have consisted predominantly of large amounts of small animals." (08-30-2017, 05:24 PM)Ngala Wrote: A new Mourasuchus (Alligatoroidea, Caimaninae) from the late Miocene of Venezuela, the phylogeny of Caimaninae and considerations on the feeding habits of Mourasuchus @Ngala Great find it was a very large crocodile based on the measurement of the skull pictured, the skull measured about 100 cent long, if you multiplly its length by 8 the total length of that croc was about 8 meters long. (26,2 ft)
Kaprosuchus "BoarCroc"
The name means "boar crocodile" from the Greek κάπρος, kapros ("boar") and σοῦχος, souchos ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar. It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ZooKeys in 2009. Kaprosuchus is known from a nearly complete skull 50,7 cm in length in which the lower jaw measured 60,3 cm long, the entire animal estimated body length is approximately 3.3 metres (10.8 ft). It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits into notches in upper jaw. This type of dentition is not seen in any other known crocodyliform. Another unique characteristic of Kaprosuchus is the presence of large, rugose horns formed from the squamosal and parietal bones that project posteriorly from the skull. The restoration is based on today crocs because they only found the skull of BoarCroc.  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author
This is the monography by Paul Sereno & Hans Larsson:
Cretaceous Crocodyliforms from the Sahara Abstract: "Diverse crocodyliforms have been discovered in recent years in Cretaceous rocks on southern landmasses formerly composing Gondwana. We report here on six species from the Sahara with an array of trophic adaptations that significantly deepen our current understanding of African crocodyliform diversity during the Cretaceous period. We describe two of these species (Anatosuchus minor, Araripesuchus wegeneri) from nearly complete skulls and partial articulated skeletons from the Lower Cretaceous Elrhaz Formation (Aptian-Albian) of Niger. The remaining four species (Araripesuchus rattoides sp. n., Kaprosuchus saharicus gen. n. sp. n., Laganosuchus thaumastos gen. n. sp. n., Laganosuchus maghrebensis gen. n. sp. n.) come from contemporaneous Upper Cretaceous formations (Cenomanian) in Niger and Morocco." Full Article Reconstruction by Todd Marshall: Kaprosuchus saharicus  *This image is copyright of its original author Araripesuchus rattoides  *This image is copyright of its original author Araripesuchus wegeneri  *This image is copyright of its original author Anatosuchus minor  *This image is copyright of its original author Laganosuchus thaumastos  *This image is copyright of its original author
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