Seychelles giant tortoise
The domed carapace (to 91.5 cm) has steep sides, but is flattened dorsally, is only slightly broader posteriorly than anteriorly, and has a serrated posterior rim. A cervical scale is present, but no cervical indentation. All vertebrals are broader than long with have raised centers; vertebral 3 is longer than vertebral 2, but vertebral 4 is the longest. Vertebral 3 is the highest point of the shell, but it is only slightly higher than vertebrals 2 and 4. Vertebrals 1 and 5 slope abruptly downward. Usually 11 marginals lie on each side of the carapace, and the supracaudal (usually undivided, but occasionally divided) is either flat or downward curved between the posterior marginals. The posterior marginals are flared. The carapace is grayish-brown. The plastron is short to moderate (71-91% of carapace length), and either lacks a posterior notch or rarely has a very shallow one. The plastral formula (based on the plate in Günther, 1877) is: abd > hum > fem > gul >< pect > an. The lateral quarter of the humero-pectoral seam is angled forward at 140-145° to its main part; the abdominal-femoral seam is also angled. The bridge is moderate is size, with a small axillary and a larger inguinal. The bridge and plastron are the same color as the carapace. The head is more blunt than that of the Aldabra tortoise, with a nonprojecting snout and a slightly hooked upper jaw. The nostril shape is like that of the Aldabra tortoise. Head scalation also resembles that species. The anterior surface of the forelimbs is covered with large, nonoverlapping scales. No conical tubercles are present on the thighs.
Males are larger than females and have tails that are longer and thicker and bear a large terminal scale.
Distribution and Habitat
The eight known living individuals are in captivity on the Seychelles. One, the neotype, supposedly at least 100 years old, resided at the Casuarina Beach Hotel in Seychelles until its death in 1994. It was reported to have been kept in the mountains of Mahé prior to its purchase by the hotel, and this leads to the question of whether or not there may have been a small population of the tortoises living there in the 19th century (Gerlach and Canning, 1998).
Despite Günther's choice of the name hololissa, this turtle does not always have a smooth carapace, nor is this a distinctive feature (Justin Gerlach, pers. comm.). This species was referred to as Dipsochelys "resurrecta" by Gerlach and Canning (1996a) before its true identity was established.
IUCN Red List Status (1996)
Not included in Baillie and Groombridge (1996); the 1997 Seychelles Red Data Book (Gerlach, 1997a) considers this species Extinct in the Wild.