Crocodylus

Crocodylus is a genus of true crocodiles in the family Crocodylidae.

Crocodylus Temporal range: Late Oligocene - recent, 25–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Mugger crocodile (C. palustris)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Archosauria
Order:	Crocodilia
Family:	Crocodylidae
Subfamily:	Crocodylinae
Genus:	Crocodylus Laurenti, 1768
Type species
Crocodylus niloticus Laurenti, 1768
Species
See text
Worldwide distribution of Crocodylus
Synonyms[1]
Bombifrons Gray, 1862 Crocodillus Scopoli, 1777 Crocodilus Gmelin, 1789 Crocodilus Laurenti, 1768 Crocodylus Gronovius, 1763 Mecistops Gray, 1844 Molina Romer, 1956 Molinia Gray, 1862 Motinia Gray, 1844 Oopholis Gray, 1844 Oxycrocodylus Hoser, 2012 Palinia Gray, 1844 Philas Gray, 1874 Temsacus Gray, 1862

Taxonomy

The generic name, Crocodylus, was proposed by Josephus Nicolaus Laurenti in 1768.^[2] 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.^[3]

Extant species

The 13–14 living species are:

Image	Scientific name	Taxon authority	Common name	Distribution
	Crocodylus acutus	(Cuvier, 1807)	American crocodile	Southern Florida and the Atlantic and Pacific coasts of north Mexico to North America as far south as Peru and Venezuela, Cuba, Jamaica, Hispaniola and Grand Cayman.
	Crocodylus halli [4]	Murray, Russo, Zorrilla & McMahan, 2019	Hall's crocodile	southern New Guinea
	Crocodylus intermedius	(Graves, 1819)	Orinoco crocodile	Colombia and Venezuela
	Crocodylus johnstoni	Krefft, 1873	Freshwater crocodile	Northern regions of Australia
	Crocodylus mindorensis	Schmidt, 1935	Philippine crocodile	Northern Sierra Madre Natural Park within the Luzon rainforest, San Mariano, Isabela, Dalupiri island in the Babuyan Islands, Abra (province) in Luzon and the Ligawasan Marsh, Lake Sebu in South Cotabato, Pulangi River in Bukidnon, and possibly in the Agusan Marsh Wildlife Sanctuary in Mindanao
	Crocodylus moreletii	(A. H. A. Duméril & Bibron, 1851)	Morelet's crocodile or Mexican crocodile	Mexico, Belize and Guatemala
	Crocodylus niloticus	Laurenti, 1768	Nile crocodile or African crocodile, (the subspecies found in Madagascar, C. n. madagascariensis, is sometimes called the black crocodile)	Israel and Syria (historically), Somalia, Ethiopia, Uganda, Kenya, Egypt, the Central African Republic, the Democratic Republic of the Congo, Equatorial Guinea, Tanzania, Rwanda, Burundi, Zambia, Zimbabwe, Gabon, Angola, South Africa, Malawi, Mozambique, Sudan, South Sudan, Botswana, and Cameroon
	Crocodylus novaeguineae	Schmidt, 1928	New Guinea crocodile	northern New Guinea
	Crocodylus palustris	(Lesson, 1831)	Mugger crocodile, marsh crocodile, or Indian crocodile	southern Iran, southern Pakistan, southern Nepal, India, Sri Lanka
	Crocodylus porosus	Schneider, 1801	Saltwater crocodile or estuarine crocodile	Eastern India, Sri Lanka, Southeast Asia and Northern Australia
	Crocodylus rhombifer	(Cuvier, 1807)	Cuban crocodile	Cuba
	Crocodylus siamensis	Schneider, 1801	Siamese crocodile	Indonesia (Borneo and possibly Java), Brunei, East Malaysia, Laos, Cambodia, Myanmar, Thailand and Vietnam.
	Crocodylus suchus	Geoffroy, 1807	West African crocodile or desert crocodile	Mauritania, Benin, Liberia, Nigeria, Niger, Cameroon, Chad, Central African Republic, Equatorial Guinea, Senegal, Mali, Guinea, Gambia, Burkina Faso, Ghana, Gabon, Togo, Ivory Coast and Republic of Congo
	Crocodylus raninus (Considered to be a synonym of Crocodylus porosus; its status remains unclear).[5]	S. Müller & Schlegel, 1844	Borneo crocodile	Borneo

Fossils

Crocodylus also includes five extinct species:^[3]

• † 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 of Kenya.

Evolution

While taxonomists generally agree that the crown group of Crocodylus appeared ~16 - 14 million years ago, there is an ongoing debate discussing whether the genus has an African or Indo-Pacific origin.^[6][7] Proponents of the African origin point towards phylogenetic evidence suggesting that the most recent common ancestor of Crocodylus and its sister genus, Voay, diverged around 25 million years ago near the Oligocene/Miocene boundary.^[6] This theory is supported by the existence of closely related African genera Osteolaemus and Mecistops.^[6]

Proponents of the Indo-Pacific origin claim that the origin of the genus closely coincides with the appearance of the oldest known species, Crocodylus palaeindicus, in South Asia.^[8] Additionally, mitochondrial analysis consistently places Indo-Pacific species Crocodylus mindorensis, Crocodylus novaeguineae, and Crocodylus johnstoni in the basal-most clade of the genus.^[8][9] All known New World and African crocodylus species have a much more recent evolutionary origin.^[8] While the exact origins of the genus remain uncertain, the most recent common ancestor of the species likely utilized osmoregulatory adaptations, including lingual salt glands, to radiate across the tropics.^[7]

Phylogeny

A 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data established the inter-relationships within Crocodylidae.^[10] In 2021, Hekkala et al. were able to use paleogenomics, extracting DNA from the extinct Voay, to better establish the relationships within Crocodylidae, including the subfamilies Crocodylinae and Osteolaeminae.^[6]

The below cladogram shows the results of the latest study:

Crocodylidae

Osteolaeminae Mecistops cataphractus West African slender-snouted crocodile Euthecodon† Brochuchus† Rimasuchus† Osteolaemus osborni Osborn’s dwarf crocodile Osteolaemus tetraspis Dwarf crocodile Crocodylinae Voay† Crocodylus Crocodylus anthropophagus† Crocodylus thorbjarnarsoni† Crocodylus palaeindicus† Crocodylus Tirari Desert† Asia+Australia Crocodylus johnstoni Freshwater crocodile Crocodylus novaeguineae New Guinea crocodile Crocodylus mindorensis Philippine crocodile Crocodylus porosus Saltwater crocodile Crocodylus siamensis Siamese crocodile Crocodylus palustris Mugger crocodile Africa+New World Crocodylus checchiai† Crocodylus falconensis† Crocodylus suchus West African crocodile Crocodylus niloticus Nile crocodile New World Crocodylus moreletii Morelet's crocodile Crocodylus rhombifer Cuban crocodile Crocodylus intermedius Orinoco crocodile Crocodylus acutus American crocodile

(crown group)