What is Stupendemys?
{{Italic title}} {{Taxobox | color = lightblue | name = ''Stupendemys'' | fossil_range = late [[Miocene]] &ndash; early [[Pliocene]] 6 to 5 mya | image = Stupendemys geographicus.jpg | image_caption = ''Stupendemys geographicus'' at the [[AMNH]] | regnum = [[Animal]]ia | phylum = [[Chordata]] | subphylum = [[Vertebrata]] | superclassis = [[Tetrapoda]] | classis = [[Reptilia]] | subclassis = [[Anapsida]] | ordo = [[Testudines]] | subordo = [[Pleurodira]] | familia = [[Podocnemididae]] | genus = '''''Stupendemys''''' | genus_authority = Wood, 1976}} '''''Stupendemys''''' is a [[prehistoric]] [[genus]] of freshwater [[turtle]]. Its [[fossil]]s have been found in northern [[South America]], in rocks dating from the late [[Miocene]] to the very start of the [[Pliocene]], about 6 to 5 million years ago.<ref name = bm2006>Bocquentin, Jean & Melo, Janira 2006. ''Stupendemys souzai'' sp. nov. (Pleurodira, Podocnemididae) from the Miocene-Pliocene of the Solimões Formation, Brazil. ''Revista Brasileira de Paleontologia'' '''9'''(2): 187-192. [http://www.sbpbrasil.org/revista/edicoes/9_2/RBP9-2-Jean.pdf PDF fulltext]</ref> ''Stupendemys'''s [[carapace]] measured over {{convert|1.80|m|ft|abbr=on}} in length and was also very wide. With a total carapace length of at least 11 feet (3.3 m) it was the largest turtle that ever existed, surpassing even ''[[Archelon]]''.<ref>{{cite web|url=http://cameronmccormick.blogspot.com/2010/03/stupendemys-giant-amongst-mega-turtles.html|title=The Lord Geekington: Stupendemys: Giant Amongst Mega-Turtles|first=Cameron|last=Mccormick|date=11 March 2010|publisher=}}</ref> Two species have been described to date. ''Stupendemys geographicus'' from [[Venezuela]], and ''Stupendemys souzai'', a bit smaller and more slender, from [[Brazil]].<ref name = bm2006 /> == Ecology == Its weight helped ''Stupendemys'' stay under water for long periods, [[grazing]] on aquatic [[plant]]s. It was probably a very weak swimmer, unable to move its bulk against a swift current, and probably avoided smaller strea