Macrochelys

Last updated

Macrochelys
Temporal range: Miocene–Recent
Alligator snapping turtle.jpg
Alligator snapping turtle (Macrochelys temminckii)
Scientific classification OOjs UI icon edit-ltr.svg
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.

Contents

Extant species

Skeleton of an alligator snapping turtle (Macrochelys temminckii) on display at the Museum of Osteology Alligator Snapping Turtle Skeleton.jpg
Skeleton of an alligator snapping turtle (Macrochelys temminckii) on display at the Museum of Osteology

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]

Fossil history and extinct species

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:

Related Research Articles

<span class="mw-page-title-main">Chelydridae</span> Family of turtles

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.

<i>Chelydra</i> Genus of turtles

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.

<span class="mw-page-title-main">Chaco side-necked turtle</span> Species of turtle

The Chaco side-necked turtle is a species of turtle in the family Chelidae. It is found in Argentina, Paraguay, and possibly Bolivia. Its natural habitat is subtropical or tropical moist montane forests. The turtle possesses long horny spurs on its upper thighs. It is 18 cm in shell length. Like other members of its genus, the turtle buries itself in the mud when the streams run dry, a behaviour possibly parallel to the winter hibernating behaviours of turtles further north.

<span class="mw-page-title-main">Brazilian radiolated swamp turtle</span> Species of turtle

The Brazilian radiolated swamp turtle is a species of turtle in the Chelidae family endemic to Brazil.

<span class="mw-page-title-main">Black spine-neck swamp turtle</span> Species of turtle

The black spine-neck swamp turtle, also commonly known as the spiny-neck turtle or Spix's sideneck turtle, is a species of turtle in the family Chelidae. The species is endemic to South America, specially in the Southern Cone region.

<span class="mw-page-title-main">New Guinea snake-necked turtle</span> Species of turtle

The New Guinea snake-necked turtle is a species of turtle in the family Chelidae. The species is found almost exclusively within Western Province, Papua New Guinea.

<span class="mw-page-title-main">Parker's snake-necked turtle</span> Species of turtle

Parker's snake-necked turtle is a species of turtle in the family Chelidae.

Pritchard's snake-necked turtle is a species of turtles in the family Chelidae. The species is endemic to a restricted area of Central Province, Papua New Guinea.

<i>Elseya</i> Genus of turtles

Elseya is a genus of large side-necked turtles, commonly known as Australian snapping turtles, in the family Chelidae. Species in the genus Elseya are found in river systems in northern and northeastern Australia and throughout the river systems of New Guinea. They are identified by the presence of alveolar ridges on the triturating surfaces of the mouth and the presence of a complex bridge strut.

<span class="mw-page-title-main">New Guinea snapping turtle</span> Species of turtle

The Western New Guinea stream turtle or New Guinea snapping turtle is a species of freshwater turtle in the Chelidae family. It is found in the Bird's Head Peninsula and the Bomberai Peninsula west of Cenderawasih Bay, and on the island of Waigeo of West Papua, Indonesia.

<span class="mw-page-title-main">Red-headed Amazon River turtle</span> Species of turtle

The red-headed Amazon side-necked turtle, red-headed river turtle or red-headed sideneck is a species of turtle in the family Podocnemididae. It is found in the Amazon basin in Brazil, Colombia, and Venezuela. The red-headed river turtle is considered a small turtle with a size of less than 32 cm, making it easily distinguishable from other species in the area. Identifying factors of this turtle include colors ranging from dark brown to black, barbels under the chin, and a bright red strip that goes from behind its head to the tympanum.

<span class="mw-page-title-main">Six-tubercled Amazon River turtle</span> Species of turtle

The six-tubercled Amazon River turtle or six-tubercled river turtle is a species of turtle in the family Podocnemididae.

<i>Mesoclemmys</i> Genus of turtles

Mesoclemmys is a genus of South American turtles in the family Chelidae.

<i>Elseya dentata</i> Species of turtle

Elseya dentata, the northern snapping turtle, is a large aquatic turtle found throughout many rivers in northern Western Australia and the Northern Territory. It is one of three species in the nominate subgenus Elseya.

<i>Chelodina burrungandjii</i> Species of turtle

Chelodina (Chelydera) burrungandjii, the sandstone snake-necked turtle or Arnhem Land long-necked turtle, is a medium-sized turtle reaching carapace lengths of 316 mm. The species is found in the sandstone plateaus and escarpments and the plunge pools of Arnhem Land of the Northern Territory. The species had been long recognised as valid. However, it had been difficult to research due to the remoteness of its habitat. Efforts to breed this species in captivity had been largely unsuccessful, until National Aquarium Herpetologist Matthew Benedict lead a successful breeding project in 2021. The species occurs in proximity to Chelodina rugosa, to which it is closely related. For the most part the two species are parapatric in distribution. However, they do come together in limited locations such as plunge pools at the base of the escarpments. In these areas there is hybridization between the species.

<i>Elseya schultzei</i> Species of New Guinea turtle

Elseya schultzei, commonly known as Schultze's snapping turtle, is a species of chelid turtle endemic to northern New Guinea.

<i>Chelodina kuchlingi</i> Species of turtle

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.

<span class="mw-page-title-main">Scott A. Thomson</span> Australian herpetologist

Scott A. Thomson is an Australian herpetologist, paleontologist, and taxonomist, specialising in turtles of the family Chelidae.

Chelodina gunaleni, also known commonly as Gunalen's long-necked turtle and Gunalen's snake-necked turtle, is a species of turtle in the family Chelidae. The species is endemic to the lowlands of west-central West Papua, Indonesia, south of the central ranges.

References

  1. Rhodin, Anders G.J.; van Dijk, Peter Paul; Inverson, John B.; Shaffer, H. Bradley; Roger, Bour (2012-12-31). "Turtles of the world, 2012 update: Annotated checklist of taxonomy, synonymy, distribution and conservation status" (PDF). Chelonian Research Monographs. 5: 000.251. doi:10.3854/crm.5.000.checklist.v5.2012. ISBN   978-0965354097. Archived from the original (PDF) on 2013-06-16.
  2. Fritz, Uwe; Havaš, Peter (2007). "Checklist of Chelonians of the World". Vertebrate Zoology. 57 (2): 149–368. doi: 10.3897/vz.57.e30895 . S2CID   87809001.
  3. John R. Platt (April 17, 2014). "Alligator Snapping Turtles, the Dinosaurs of the Turtle World, Are Actually 3 at-Risk Species". Scientific American.
  4. 1 2 Reptile Database: Macrochelys. Retrieved 26 September 2017.
  5. 1 2 Turtle Taxonomy Working Group [Rhodin, A.G.J., Iverson, J.B., Bour, R. Fritz, U., Georges, A., Shaffer, H.B., and van Dijk, P.P.] (2017). "Turtles of the World: Annotated Checklist and Atlas of Taxonomy, Synonymy, Distribution, and Conservation Status (8th Ed.)." In: Rhodin, A.G.J., Iverson, J.B., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Pritchard, P.C.H., and Mittermeier, R.A. (Eds.). "Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group." Chelonian Research Monographs 7:1–292. doi : 10.3854/crm.7.checklist.atlas.v8.2017.
  6. 1 2 3 Thomas, T., Granatosky, M. Bourque, J., Krysko, K., Moler, P., Gamble, T., Suarez, E., Leone, E., Enge, K. & Roman, J. (2014). "Taxonomic assessment of Alligator Snapping Turtles (Chelydridae: Macrochelys), with the description of two new species from the southeastern United States." Zootaxa 3786(2): 141–165.
  7. Joshua E. Brown (April 24, 2014). "Research splits alligator snapping turtle, 'dinosaur of the turtle world,' into three species". Phys.org.
  8. Folt, B.; and C. Guyer (2015). "Evaluating recent taxonomic changes for alligator snapping turtles (Testudines: Chelydridae)." Zootaxa 3947(3): 447–450.
  9. J. Howard Hutchison (2008). "History of fossil Chelydridae". In A.C. Styermark; M.S. Finkler; R.J. Brooks (eds.). Biology of the Snapping Turtle (Chelydra serpentina). Johns Hopkins University Press. pp. 14–30.