Osteolaemus

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Osteolaemus
Crocodile nain aquarium porte doree Paris.JPG
Dwarf crocodile
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Clade: Archosauriformes
Order: Crocodilia
Family: Crocodylidae
Subfamily: Osteolaeminae
Genus: Osteolaemus
Cope, 1861
Type species
Osteolaemus tetraspis
Cope, 1861
Species

2, see text.

Osteolaemus is a genus of crocodiles. [1] [2] [3] They are small, secretive crocodiles that occur in wetlands of West and Middle Africa. They are commonly known as the African dwarf crocodiles. [2] Unlike other crocodiles, Osteolaemus are strictly nocturnal. [3]

Species

The following species are recognized as being valid. [1]

ImageScientific nameCommon nameDistribution
Osteolaemus osborni 88103967.jpg Osteolaemus osborni Schmidt, 1919Congo dwarf crocodileCongo River basin of Central Africa
Osteolaemus tetraspis - Karlsruhe Zoo 02.jpg Osteolaemus tetraspis Cope, 1861dwarf crocodile, African dwarf crocodile, broad-snouted crocodile, bony crocodileWest Africa and Ogooué River basin of Central Africa
Nota bene : A binomial authority in parentheses indicates that the species was originally described in a genus other than Osteolaemus.

Molecular data suggest that Osteolaemus tetraspis consists of two lineages that would warrant recognition as distinct species. [2]

Related Research Articles

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Crocodiles 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, the gharial and false gharial among other extinct taxa.

<span class="mw-page-title-main">Crocodylinae</span> Subfamily of crocodiles

Crocodylinae is a subfamily of true crocodiles within the family Crocodylidae, and is the sister taxon to Osteolaeminae.

<span class="mw-page-title-main">Gavialidae</span> Family of gharial crocodylians

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<span class="mw-page-title-main">Osteolaeminae</span> Subfamily of crocodiles

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<i>Kinyang</i> (genus) Extinct genus of reptiles

Kinyang is an extinct genus of osteolaemine crocodile from the Early to Middle Miocene of Kenya. Two species are currently known, K. mabokoensis from the Lake Victoria basin and K. tchernovi from the Lake Victoria and Lake Turkana basin. Kinyang had an exceptionally broad and robust skull, much wider than that of any living crocodile species. This might have allowed it to attack and kill prey its own size or even bigger. Kinyang is notably larger than its contemporary relative Brochuchus. While the precise reasons for the extinction of Kinyang are not known, it coincides with a larger faunal turnover that saw osteolaemines replaced by the still dominant crocodylines. One reason for this shift may have been the drying climate of Africa at the time, which caused rainforests to be replaced by more open environments and disrupted the nesting behavior of osteolaemines due to their dependence on foliage.

References

  1. 1 2 Osteolaemus at the Reptarium.cz Reptile Database. Accessed 3 January 2023.
  2. 1 2 3 Eaton, Mitchell J.; Martin, Andrew; Thorbjarnarson, John & Amato, George (2009). "Species-level diversification of African dwarf crocodiles (genus Osteolaemus): A geographic and phylogenetic perspective". Molecular Phylogenetics and Evolution. 50 (3): 496–506. doi:10.1016/j.ympev.2008.11.009.
  3. 1 2 Vitt, Laurie J. & Caldwell, Janalee P. (2014). Herpetology: An Introductory Biology of Amphibians and Reptiles (4th ed.). Academic Press. pp. 550–552. OCLC   839312807.