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Mecistops
''Mecistops'' is a genus of crocodiles, the slender-snouted crocodiles, native to sub-Saharan Africa. Taxonomy and etymology Traditionally placed in '' Crocodylus'', recent studies in DNA and morphology have shown that it is in fact basal to ''Crocodylus'', thus was moved its own genus. This genus itself was long considered to contain only one species, '' M. cataphractus'', but recent genetic analysis has revealed the existence of two species: the West African slender-snouted crocodile (''M. cataphractus'') and the Central African slender-snouted crocodile (''M. leptorhynchus''). Both species diverged during the Miocene (about 6.5–7.5 million years ago) and are separated by the Cameroon Volcanic Line. Phylogeny The cladogram below is based on two studies that combined morphological and molecular (DNA sequencing) data. (Note that most morphological analyses find a closer relationship between ''Euthecodon'' and '' Brochuchus''.) Alternatively, other morphological studies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central African Slender-snouted Crocodile
The Central African slender-snouted crocodile (''Mecistops leptorhynchus'') is one of two species of crocodiles in the genus ''Mecistops''. It was once thought to be a population of the West African slender-snouted crocodile (''Mecistops cataphractus'') but was elevated to a species after two detailed studies, one in 2014 and the other in 2018. The species was described in 1835 on the basis of a specimen that had died at the London Zoo and had been claimed to have been collected in the Fernando Po. Studies of specimens and their molecular sequences established that there were two different species which occurred in distinct hydrological zones. ''M. leptorhynchus'' is easily differentiated morphologically from ''M. cataphractus'' by the absence of a round tubercle or boss on the squamosal scale at the back of the head in the former and present in the latter. Etymology The generic name ''Mecistops'' is most probably derived from the Ancient Greek words μήκιστ (''mēkist' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mecistops Leptorhynchus
The Central African slender-snouted crocodile (''Mecistops leptorhynchus'') is one of two species of crocodiles in the genus ''Mecistops''. It was once thought to be a population of the West African slender-snouted crocodile (''Mecistops cataphractus'') but was elevated to a species after two detailed studies, one in 2014 and the other in 2018. The species was described in 1835 on the basis of a specimen that had died at the London Zoo and had been claimed to have been collected in the Fernando Po. Studies of specimens and their molecular sequences established that there were two different species which occurred in distinct hydrological zones. ''M. leptorhynchus'' is easily differentiated morphologically from ''M. cataphractus'' by the absence of a round tubercle or boss on the squamosal scale at the back of the head in the former and present in the latter. Etymology The generic name ''Mecistops'' is most probably derived from the Ancient Greek words μήκιστ (''mēkist' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West African Slender-snouted Crocodile
The West African slender-snouted crocodile (''Mecistops cataphractus''), or slender-snouted crocodile, is a critically endangered species of African crocodile. It is one of five species of crocodile in Africa, the other four being the Central African slender-snouted, Nile, West African and dwarf crocodiles. The slender-snouted crocodile (''M. cataphractus'') was thought to be distributed across west Africa and into central Africa but the central African species has been separated as the Central African slender-snouted crocodile (''M. leptorhynchus'') based on studies in 2014 and 2018 that indicated that both were distinct species. The name ''cataphractus'' is retained for the West African species as that species was described first based on specimens from western Africa. The two species diverged about 6.5–7.5 mya, living in different river drainage zones that were geographically separated from each other by the Cameroon Line. Etymology The genus name ''Mecistops'' is most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteolaeminae
Osteolaeminae is a subfamily of true crocodiles within the family Crocodylidae containing the dwarf crocodiles and slender-snouted crocodiles, and is the sister taxon to Crocodylinae. Taxonomy Osteolaeminae was named by Christopher Brochu in 2003 as a subfamily of Crocodylidae separate from Crocodylinae, and is cladistically defined as ''Osteolaemus tetraspis'' (the Dwarf crocodile) and all crocodylians more closely related to it than to ''Crocodylus niloticus'' (the Nile crocodile). This is a stem-based definition, and is the sister taxon to Crocodylinae. Osteolaeminae contains the two extant genera ''Osteolaemus'' and ''Mecistops'', along with several extinct genera, although the number of extant species within Osteolaeminae is currently in question. Phylogeny The cladogram below is based on two studies that combined morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data. Alternatively, other morphological studies have recovered ''Mecistops'' a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mecistops Cataphractus
The West African slender-snouted crocodile (''Mecistops cataphractus''), or slender-snouted crocodile, is a critically endangered species of African crocodile. It is one of five species of crocodile in Africa, the other four being the Central African slender-snouted, Nile, West African and dwarf crocodiles. The slender-snouted crocodile (''M. cataphractus'') was thought to be distributed across west Africa and into central Africa but the central African species has been separated as the Central African slender-snouted crocodile (''M. leptorhynchus'') based on studies in 2014 and 2018 that indicated that both were distinct species. The name ''cataphractus'' is retained for the West African species as that species was described first based on specimens from western Africa. The two species diverged about 6.5–7.5 mya, living in different river drainage zones that were geographically separated from each other by the Cameroon Line. Etymology The genus name ''Mecistops'' is most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodile
Crocodiles (family (biology), family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant taxon, extant members of the order (biology), order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological family (biology), families. The gharial, with its narrow snout, is easier to distinguish, while Morphology (biology), morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylidae
Crocodiles (family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to include all extant members of the order Crocodilia, which includes the alligators and caimans (family Alligatoridae), the gharial and false gharial (family Gavialidae) among other extinct taxa. Although they appear similar, crocodiles, alligators and the gharial belong to separate biological families. The gharial, with its narrow snout, is easier to distinguish, while morphological differences are more difficult to spot in crocodiles and alligators. The most obvious external differences are visible in the head, with crocodiles having narrower and longer heads, with a more V-shaped than a U-shaped snout compared to alligators and caimans. Another obvious trait is that the upper and lower jaws of the crocodiles are the same width, and the teeth in the lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euthecodon
''Euthecodon'' is an extinct genus of long-snouted crocodile. It was common throughout much of Africa during the Neogene, with fossils being especially common in Kenya, Ethiopia, and Libya. Although superficially resembling that of gharials, the long snout was a trait developed independently from that of other crocodilians and suggests a diet of primarily fish. ''Euthecodon'' coexisted with a wide range of other crocodiles in the areas it inhabited before eventually going extinct during the Pleistocene. Discovery and naming The first remains of ''Euthecodon'' were described by French paleontologist Léonce Joleaud based on material collected by the Bourg de Bozas expedition between 1900 and 1903 in Ethiopia.Joleaud, L. (1920). Sur la présence d'un Gavialide du genre ''Tomistoma'' dans le Pliocène d'eau douce de l'Ethiopie. ''Comptes Rendus de l'Académie des Sciences'' 70:816-818. These remains, thought to belong to a species of false gharial, were first described in 1920 under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylinae
Crocodylinae is a subfamily of true crocodiles within the family Crocodylidae, and is the sister taxon to Osteolaeminae ( dwarf crocodiles and slender-snouted crocodiles). Taxonomy Crocodylinae was cladistically defined by Christopher Brochu in 1999 as ''Crocodylus niloticus'' (the Nile crocodile) and all crocodylians more closely related to it than to ''Osteolaemus tetraspis'' (the Dwarf crocodile). This is a stem-based definition, and is the sister taxon to Osteolaeminae. Crocodylinae contains the extant genus '' Crocodylus''. It is disputed as to whether is also includes ''Mecistops'' (slender-snouted crocodiles), or the extinct genus Voay. Phylogeny Some morphological studies have recovered ''Mecistops'' as a basal member of Crocodylinae, more closely related to '' Crocodylus'' than to ''Osteolaemus'' and the other members of Osteolaeminae, as shown in the cladogram below. The below cladogram is based on a 2021 study using paleogenomics that extracted DNA from the ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylus
''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 species. There are additional extinct species attributed to the genus ''Crocodylus'' that studies have shown no longer belong, although they have not yet been reassigned to new genera. Extant species The 13–14 living species are: Fossils ''Crocodylus'' also includes five extinct species: * † '' Crocodylus anthropophagus'' is an extinct crocodile from Plio-Pleistocene of Tanzania. * † ''Crocodylus checchiai'' is an extinct crocodile from Late Miocene of Kenya. * † ''Crocodylus falconensis'' is an extinct crocodile from Early Pliocene of Venezuela. * † ''Crocodylus palaeindicus'' is an extinct crocodile the Miocene to the Pleistocene of southern Asia. * † ''Crocodylus thorbjarnarsoni'' is an extinct crocodile from Plio-Pleistocene o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rimasuchus
''Rimasuchus'' is an extinct genus of crocodile from the Miocene of Egypt and possibly Libya. Only one species - ''Rimasuchus lloydi'' - is currently known. It was previously thought to be a species of ''Crocodylus'', but is now thought to be more closely related to the modern African dwarf crocodiles (''Osteolaemus''). History and naming The first fossil of ''Rimasuchus'' an incomplete skull with associated mandible, was collected by lieutenant colonel Arthur H. Lloyd in the early 20th century in Wadi Moghara, Egypt. The holotype specimen, CGM 15597, was given to the Egyptian Geological Museum and described by Fourtau in 1920 under the name ''Crocodylus lloydi''. Other material includes an uncatalogued skull housed at the Natural History Museum, London (likewise from Wadi Moghara) and fossils found at Gebel Zelten in Libya. Eventually other skulls further south in Africa ended up being assigned to ''"Crocodylus" lloydi'' , with the oldest and southern-most material stemming fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylus Thorbjarnarsoni
''Crocodylus thorbjarnarsoni'' is an extinct species of crocodile from the Pliocene and Pleistocene of the Turkana Basin in Kenya. It is closely related to the species ''Crocodylus anthropophagus'', which lived during the same time in Tanzania. ''C. thorbjarnarsoni'' could be the largest known true crocodile, with the largest skull found indicating a possible total length up to . It may have been a predator of early hominins. ''Crocodylus thorbjarnarsoni'' was named by Christopher Brochu and Glenn Storrs in 2012 in honor of John Thorbjarnarson, a conservationist who worked to protect endangered crocodilians. Description ''Crocodylus thorbjarnarsoni'' is distinguished from other crocodiles by its broad snout. It has small raised rims on the prefrontal bones in front of the eyes, a feature also seen in some Nile crocodile individuals. The squamosal bones form raised rims along the sides of the skull table, similar to the crests in ''C. anthropophagus'' but much smaller. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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