The Aldabra giant tortoise (Aldabrachelys gigantea) is a species of tortoise in the family Testudinidae. The species is endemic to the Seychelles, with the nominate subspecies, A. g. gigantea native to Aldabra atoll. It is one of the largest tortoises in the world. Historically, giant tortoises were found on many of the western Indian Ocean islands, as well as Madagascar, and the fossil record indicates giant tortoises once occurred on every continent and many islands with the exception of Australia and Antarctica. Many of the Indian Ocean species were thought to be driven to extinction by over-exploitation by European sailors, and they were all seemingly extinct by 1840 with the exception of the Aldabran giant tortoise on the island atoll of Aldabra. Although some remnant individuals of A. g. hololissa and A. g. arnoldi may remain in captivity, in recent times, these have all been reduced as subspecies of A. gigantea. Description The carapace of A. gigantea is a brown or tan in color with a high, domed shape. The species has stocky, heavily scaled legs to support its heavy body. The neck of the Aldabra giant tortoise is very long, even for its great size, which helps the animal to exploit tree branches up to a meter from the ground as a food source. Similar in size to the famous Galápagos giant tortoise, its carapace averages in length with an average weight of . Females are generally smaller than males, with average specimens measuring in carapace length and weighing . Medium-sized specimens in captivity were reported as in body mass. Another study found body masses of up to most commonplace. Nomenclature and systematics This species is widely referred to as Aldabrachelys gigantea, but in recent times, attempts were made to use the name Dipsochelys as Dipsochelys dussumieri. After a debate that lasted two years with many submissions, the ICZN eventually decided to conserve the name Testudo gigantea over this recently used name (ICZN 2013). This also affected the genus name for the species, establishing Aldabrachelys gigantea as nomen protectum. Four subspecies are currently recognized. A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other than Aldabrachelys: A. g. gigantea , Aldabra giant tortoise from the Seychelles island of Aldabra A. g. arnoldi , Arnold's giant tortoise from the Seychelles island of Mahé A. g. daudinii † , Daudin's giant tortoise, from the Seychelles