Macrochelys Temporal range: | |
---|---|
Alligator snapping turtle (Macrochelys temminckii) | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Testudines |
Suborder: | Cryptodira |
Family: | Chelydridae |
Genus: | Macrochelys Gray, 1856 [1] |
Type species | |
Macrochelys temminckii Troost, 1835 | |
Synonyms [2] | |
Macrochelys is a genus of very large freshwater turtles in the family Chelydridae, native to the Southeastern and Midwestern United States. Only a single extant species was recognized until 2014, when a study divided it into two or possibly three species. [3] These turtles are easily recognized by three distinct dorsal ridges with raised spikes.
Traditionally, only a single extant species (M. temminckii) was recognized, but following reviews, two species are now recognized: [4] [5] Anatomical differences between the two species of Macrochelys include the shape of the caudal notch at the rear of the carapace and the angle of the squamosal bone at the rear of the skull. [6] The two species are estimated to have diverged less than 3.5 million years ago. [6]
A third species has been proposed, [6] [7] but its validity is disputed. [8] Neither the Reptile Database [4] nor IUCN's Tortoise and Freshwater Turtle Specialist Group recognize it as separate from M. temminckii. [5]
Unlike the family Chelydridae as a whole, the genus Macrochelys is exclusively North American. Hutchison (2008) considered the genus Chelydrops to be a junior synonym of Macrochelys, and recombined its type species, Chelydrops stricta from the Miocene (Early Barstovian) of Nebraska, as the (then) fourth species of Macrochelys. [9]
There are two other species known only from fossil remains:
The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, Chelydra and Macrochelys. Both are endemic to the Western Hemisphere. The extinct genera are Acherontemys, Chelydrops, Chelydropsis, Emarginachelys, Macrocephalochelys, Planiplastron, and Protochelydra.
Chelydra is one of the two extant genera of the snapping turtle family, Chelydridae, the other being Macrochelys, the much larger alligator snapping turtle. The snapping turtles are native to the Americas, with Chelydra having three species, one in North America and two in Central America, one of which is also found in northwestern South America.
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Elseya schultzei, commonly known as Schultze's snapping turtle, is a species of chelid turtle endemic to northern New Guinea.
Chelodina (Chelydera) kuchlingi, commonly known as Kuchling's long-necked turtle or Kuchling's turtle, is a species of freshwater turtle in the family Chelidae. The species is endemic to Australia.
The Apalachicola snapping turtle is a proposed species that lives in the Apalachicola River, United States. The proposed species can as well be found within other panhandle rivers within the states of Florida, Georgia, and Alabama.
Scott A. Thomson is an Australian herpetologist, paleontologist, and taxonomist, specialising in turtles of the family Chelidae.
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