Megalochelys

Megalochelys ("great turtle") is an extinct genus of tortoises that lived from the Miocene to Pleistocene. They are noted for their giant size, the largest known for any tortoise, with a maximum carapace length of over 2 m (6.5 ft) in M. atlas. The genus ranged from western India and Pakistan to as far east as Sulawesi and Timor in Indonesia, though the island specimens likely represent distinct species.

== Description == One species of Megalochelys, M. atlas, is the largest known tortoise, with shells of in length having been reported. Popular weight estimates for this taxon have varied greatly with the highest estimates reaching up to in some instances. However, weights based on volumetric displacement of the skeleton suggest a mass of around . M. atlas is thus the largest known tortoise. Some island species were considerably smaller, with the Philippine species Megalochelys sondaari only having a carapace length of . The shell of Megalochelys is prominently domed, proportionally wide, with large openings for the limbs, and is relatively thin despite its size, though the epiplastron (the frontmost-portion of the lower carapace) was forked and very thick. Such forked epiplastra are found in some living tortoises, where they are used for combat and shoving contests between males. The skull of Megalochelys could grow over in length, and had a deep nasal region and a deep and rather short snout, similar to living Aldabra giant tortoises.