The African spurred tortoise (Centrochelys sulcata), also called the sulcata tortoise, is an endangered species of tortoise inhabiting the southern edge of the Sahara Desert and the Sahel. It is the largest mainland species of tortoise in Africa, and the third-largest in the world, after the Galapagos tortoise and Aldabra giant tortoise. It is the only living species in its genus, Centrochelys.
Taxonomy and etymology
In 1779 the English illustrator John Frederick Miller included a hand-coloured plate of the African spurred tortoise in his Icones animalium et plantarum and coined the binomial name Testudo sulcata. Its specific name sulcata is from the Latin word sulcus meaning "furrow" and refers to the furrows on the tortoise's scales. The species was subsequently given other binomial names. There are no recognized subspecies despite there being two separate populations, one in Western Africa and the other in Eastern Africa. There are also three different, yet similar, haplotypes. One haplotype is found in and closely around Sudan, another is found in the western portion of their range, and the last haplotype is found in Senegal, Mali, and Sudan. They are found on hills, stable dunes, and flat areas with shrubs and high grass. They also like to settle in areas with interrupted streams or rivers. This is known as aestivation. In the wild, they may burrow very deep, up to 15 m deep and 30 m long. Plants such as grasses and succulents grow around their burrows if kept moist, and in nature they continue to grow for the tortoise to eat if the soil is replenished with its feces. The species is the largest of the mainland tortoises. Despite being the largest tortoise in Africa, hatchlings measure merely about 44 millimeters and weigh around 40 grams.
Diet
Sulcata tortoises are mostly herbivores. Their overall diet should be high in fiber and very low in protein. Too much protein will lead to the tortoise growing too fast, which can result in metabolic bone disease, a condition that is characterized by distortion of the skeleton and weakened bone structure and can lead to lameness, lower quality of life, and/or shortened lifespan. Flowers and other plants including cactus pads can be consumed. In the wild, they have been observed to also eat plants and algae off the surface of the water. Studies suggest that African spurred tortoises exist in approximately 16.7% of the area where they had previously been found. These studies also show an average of 1–5 tortoises per site canvassed which indicates a rapid decline of the species. They also face threats from the pet trade as they are over harvested from their natural environment. Other threats that the species face are habitat loss due to climate change and predators which hunt the tortoises or their eggs. This means that the tortoises are able to easily to adapt back into their native savanna environments from domestic environment.
Life in captivity
thumb|African spurred tortoise at the [[Las Vegas Zoo]]
Behavior
African spurred tortoises are passive and docile pets. They are almost never aggressive and barely ever show territorial behavior. This docile behavior is complemented by their slow speed and silence. Despite their docile attitude, the tortoises should not be handled often as handling will cause stress, which can lead to health problems and premature death. Being off the ground or constantly carried can cause them to become stressed. Stressed tortoises may urinate or defecate, try to get away, hide in the shell, and hiss. They are also very curious and can end up stuck on their backs, needing help getting flipped back over. African Spurred Tortoises have a lifespan of around 70 years, which means that they are a long term commitment.