The Saddle-backed Mauritius Giant Tortoise, as its name implies, was endemic to the island of Mauritius (including several of the smaller offshore islets), Mascarene Islands in the Indian Ocean.
The species had a saddle-shaped carapace, a somewhat upright stand and was adapted for brousing higher vegetation.
When the Mascarene Islands were settled by Europenas in the 16th century, thousands of the endemic tortoise species were slaughtered for their meat and imported feral animals like cats, pigs and rats fed on the tortoises eggs and hatchlings.
The Saddle-backed Mauritius Giant Tortoise was extinct on Mauritius by the beginning of the 18th century, but a small population survived on the offshore Round Island for some additional decades. This last population, however, was doomed, its small island refuge was overrun by introduced goats and rabbits which finally destroyed the whole vegetation, leaving the tortoises starving to dead at around 1845.
The Reunion Giant Tortoise was described in 1783, it was endemic to the island of Réunion, Mascarene Islands in the Indian Ocean, where it formerly was extremely numerous, forming large herds.
The species was the largest within its genus, with carapace lenghts of 0,5 to 1,1 m.
There appear to have been both dome-shaped as well as saddle-shaped individuals in this species and they may in fact constitute two distinct species, as it is the case on the two neigboring islands of Mauritius and Rodrigues, which each harbored two endemic tortoise species once.
The tortoises were killed by the first European settlers but also caught in vast numbers by sailors to be stacked into the holds of their ships, where they, simply being turned on their backs condemned to die a horrible slow death, provided a source of fresh meat for months.
The species disappeared at the beginning of the 18th century with the last remaining individuals surviving in hidden spots on the highlands until around 1840.