The alligator snapping turtle (Macrochelys temminckii) is one of the largest freshwater turtles in the world. It is not closely related to, but is often associated with the common snapping turtle. They are the sole living member of the genus Macrochelys--while common snappers are in the genus Chelydra

Chelydra

Chelydra is one of the two extant genera of the Chelydridae family of turtles, the other being Macrochelys.-Species:The genus Chelydra has three species.* Chelydra acutirostris Peters, 1962 – South American snapping turtle...

. The epithet temminckii is in honor of Dutch zoologist

Zoology

Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...

 Coenraad Jacob Temminck

Coenraad Jacob Temminck

Coenraad Jacob Temminck was a Dutch aristocrat and zoologist.Temminck was the first director of the National Natural History Museum at Leiden from 1820 until his death. His Manuel d'ornithologie, ou Tableau systematique des oiseaux qui se trouvent en Europe was the standard work on European birds...

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The largest freshwater turtle in North America, the alligator snapper keeps to primarily southern U.S.