Crocodylus
   HOME

TheInfoList



OR:

''Crocodylus'' is a
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of true crocodiles in the family
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 me ...
.


Taxonomy

The
generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...
name, ''Crocodylus'', was proposed by
Josephus Nicolaus Laurenti Josephus Nicolaus Laurenti (4 December 1735, Vienna – 17 February 1805, Vienna) was an Austrian naturalist and zoologist of Italian origin. Laurenti is considered the auctor of the class Reptilia ( reptiles) through his authorship of ' (176 ...
in 1768. ''Crocodylus'' contains 13–14 extant (living) species and 5
extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
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 Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
.


Extant species

The 13–14 living species are:


Fossils

''Crocodylus'' also includes five
extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...
: * † ''
Crocodylus anthropophagus ''Crocodylus anthropophagus'' is an extinct species of crocodile from the Pleistocene of Tanzania. It lived 1.84 million years ago. It was a large-sized predator reaching a length of . Etymology ''Crocodylus anthropophagus'' was first named by ...
'' 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 of Kenya.


Evolution

''Crocodylus'' likely originated in Africa and radiated outwards towards Southeast Asia and the Americas, although an Australia/Asia origin has also been considered.
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 ...
evidence supports ''Crocodylus'' diverging from its closest recent relative, the extinct ''
Voay ''Voay'' is an extinct genus of crocodile from Madagascar that lived during the Late Pleistocene to Holocene, containing only one species, ''V. robustus''. Numerous subfossils have been found, including complete skulls, noted for their distinctiv ...
'' of
Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Afric ...
, around 25 million years ago, near the
Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but t ...
/
Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...
boundary.


Phylogeny

A 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (
DNA sequencing DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. T ...
), and stratigraphic (
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 ...
age) data established the inter-relationships within
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 me ...
. In 2021, Hekkala ''et al.'' were able to use paleogenomics, extracting DNA from the extinct ''
Voay ''Voay'' is an extinct genus of crocodile from Madagascar that lived during the Late Pleistocene to Holocene, containing only one species, ''V. robustus''. Numerous subfossils have been found, including complete skulls, noted for their distinctiv ...
'', to better establish the relationships within Crocodylidae, including the subfamilies
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 ...
and
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 ...
. The below cladogram shows the results of the latest study:


References

{{Taxonbar, from=Q309495 Crocodylidae Extant Miocene first appearances Reptile genera Taxa named by Josephus Nicolaus Laurenti