There is a Stupendemys geographicus specimen (UNEFM−CIAPP−2002−0) with a straight carapace length of 3.3 meters.
Scheyer, T. & Sánchez-Villagra, M. (2007) Carapace bone histology in the giant pleurodiran turtle
Stupendemys geographicus: Phylogeny and function. Acta Palaeontol. Pol. 52 (1): 137–154
One Archelon collected from South Dakota is frequently described as "16 feet from snout to tail" although what this means for straight carapace length is unclear. I'm not aware of it being properly described anywhere.
You can also choose to receive updates via daily or weekly email digests. If you are following multiple preprints then we will send you no more than one email per day or week based on your preferences.
Note: You are now also subscribed to the subject areas of this preprint and will receive updates in the daily or weekly email digests if turned on. You can add specific subject areas through your profile settings.
Usage since published - updated daily