Crocodylus is a genus in the family Crocodylidae. The scientific name was proposed by Josephus Nicolaus Laurenti in 1768.
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1. True crocodiles are members of the genus Crocodylus. A broader definition of crocodiles includes all members of the family Crocodylidae.
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Charactosuchus is an extinct genus of crocodilian. It was assigned to the family Crocodylidae in 1988.Carroll, R. L.(1988). Vertebrate Paleontology and Evolution.
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P. Willis, P. Murray, and D. Megirian. 1990. Baru darrowi gen. et sp. nov., a large, broad-snouted crocodyline (Eusuchia: Crocodylidae) from mid-Tertiary freshwater limestones in Northern Australia.
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Euthecodon was originally considered a tomistomine crocodilian. It has even been suggested to be a direct offshoot of Eogavialis.Tchernov, E. (1976). Crocodylidae from the Pliocene/Pleistocene formations of the Rudolf Basin.
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A phylogenetic analysis published in 2013 found that Brochuchus was a close relative of Osteolaemus. Brochuchus and Osteolaemus are part of a clade within Crocodylidae informally called "osteolaemins". They are closely related to the genus Crocodylus, which includes most living crocodiles. Osteolaemins are among the most diverse groups within Crocodylidae, including the small-bodied and short-snouted Osteolaemus, the generalized and longer-snouted Brochuchus, the moderate-sized and horned Voay, and the very large-bodied Rimasuchus.
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When it was described in 1983, along with a number of other reptile species, Tzaganosuchus was put in the subfamily Crocodylinae, which contains the genus Crocodylus and virtually all extant crocodile species and is the largest the three Crocodylidae subfamilies.
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Planocrania is an extinct genus of crocodylians.Planocrania in the Paleobiology Database Planocrania was once included in the family Pristichampsidae along with the genus Pristichampsus. Both genera were previously assigned to the subfamily Pristichampsinae within the family Crocodylidae before they were placed in their own family, the Pristichampsidae. Two species are currently known to belong to the genus.
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The crocodylian family Crocodylidae includes the true crocodiles, which are the members of the subfamily Crocodylinae, as well as potentially the false gharial, the only extant member of the subfamily Tomistominae. The latter is a subject of controversy as to whether it is a crocodile or actually belongs in the family Gavialidae. Further genetic analysis has to be done to come to a final conclusion.
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However, the authors suggested that the lack of differences was due to limited specimen sampling, and considered the two species to be distinct. This analysis found weak support for the clade Osteolaeminae. Brochu named Osteolaeminae in 2003 as a subfamily of Crocodylidae separate from Crocodylinae, but the group has since been classified within Crocodylinae. It includes the living genus Osteolaemus as well as the extinct species Voay robustus and Rimasuchus lloydi.
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Crocodiles (subfamily Crocodylinae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. Crocodylinae, all of whose members are considered true crocodiles, is classified as a biological subfamily. A broader sense of the term crocodile, Crocodylidae that includes Tomistoma, is not used in this article. The term crocodile here applies to only the species within the subfamily of Crocodylinae.
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The two extant genera of true crocodiles, Crocodylus and Osteolaemus, are in the subfamily Crocodylinae. Even according to traditional classification, the Tomistoma is not a true crocodile, though it is a member of the family Crocodylidae. Latest molecular evidence points to an even greater difference, creating the possibility that in fact Tomistoma is genetically closer to the gharial than true crocodiles. If proven, the species will be classified under the family Gavialidae.
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Gavialidae is a family of reptiles within the order Crocodilia. Gavialidae have conventionally consisted of only one surviving species, the gharial (Gavialis gangeticus), which is native to India and Nepal. Many extinct species are also known. The false gharial (Tomistoma schlegelii) has usually been thought to be a member of the family Crocodylidae based on several characters including skull morphology, but has sometimes been viewed as a member of this family due to general similarities in morphology and habit.
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Borealosuchus wilsoni The phylogenetic relationships of crocodilians has been the subject of debate and conflicting results. Many studies and their resulting cladograms, or "family trees" of crocodilians, have found the "short-snouted" families of Crocodylidae and Alligatoridae to be close relatives, with the long-snouted Gavialidae as a divergent branch of the tree. The resulting group of short-snouted species, name Brevirostres, was supported mainly by studies which analyzed skeletal features alone. In 2012, Erickson et al.
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Brochuchus has a generalized crocodylid body form with a long, narrow snout and a robust skeleton. Like most other species within Crocodylidae, Brochuchus was probably predatory and likely spent much of its time in water. As shown by the many mammal fossils that have been found on Rusinga Island, Brochuchus lived alongside several species of proboscideans (elephant relatives) and primates, the most famous of which is the early ape Proconsul. Although there is no direct evidence for what Brochuchus ate, it may have preyed on Proconsul.
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Mekosuchinae is an extinct subfamily of crocodylids from Australia and the South Pacific. They first appear in the fossil record in the Eocene in Australia, and survived until the arrival of humans: in the Pleistocene in Australia and within the Holocene in the Pacific islands of Fiji, New Caledonia and Vanuatu. There is however disagreement on whether or not Mekosuchinae is a true subfamily within Crocodylidae, or a distinct crocodilian family in its own right, Mekosuchidae, within the superfamily Crocodyloidea. Mekosuchine crocodiles are a diverse group.
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A total of three extant genera are placed in the family Crocodylidae, including a total of 15 species, including the desert crocodile, which is now accepted as a true species rather than a subspecies of the Nile crocodile. Recent studies suggest the dwarf crocodile, Osteolaemus tetraspis, is not a single, but two or even three species, and that the slender-snouted crocodile is two species. If so, the species count of extant crocodiles would be 18 or 19, putting the extant crocodylian species to a total of 28 or 29 instead of 25.
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The type species of Dollosuchus is D. dixoni. Many other species that once belonged to other genera have been proposed as members of the genus, but little work has been published to support these claims. Charactosuchus kugleri, another Eocene crocodilian, has been suggested to be synonymous with Dollosuchus, but this is no longer likely because C. kugleri is now thought to be a member of the family Crocodylidae, and thus closer related to modern crocodiles than to gharials. It has been suggested that Kentisuchus spenceri, Megadontosuchus arduini, and Dollosuchus dixoni are cogeneric.
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From their research, they confirmed that the two species of gharials were indeed sister taxa, meaning that the shared traits between Tomistoma and true crocodiles were a result of homoplasy. They also concluded that the only possible explanation for the data placing thoracosaurs within the gharial lineage was a significant amount of homoplastic convergence between thoracosaurs and Gavialis. Molecular studies consistently and unambiguously show the Gavialidae to be a sister group of the Crocodylidae to the exclusion of Alligatoridae, rendering Brevirostres paraphyletic and Gavialoidea perhaps polyphyletic. The clade including crocodiles and gharial has been suggested to be called Longirostres.
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Crocodilia (or Crocodylia) 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 living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the order's total group, the clade Pseudosuchia, appeared about 250 million years ago in the Early Triassic period, and diversified during the Mesozoic era. The order Crocodilia includes the true crocodiles (family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae).
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Despite the results of the phylogenetic analysis, "A." germanicus is an unlikely candidate for the ancestor of mekosuchines because it lived very far from Australia and the likelihood that it could have reached Australia from Europe is very low. More recent phylogenetic analyses place Mekosuchinae as a clade within the family Crocodylidae, a deeply nested position that is far from Asiatosuchus. Most phylogenetic analyses do not support the idea that all species of Asiatosuchus belong to their own clade. Instead they find that Asiatosuchus species form a paraphyletic grouping, meaning that Asiatosuchus represents an evolutionary grade of successively more derived crocodyloids rather than its own separate lineage.
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