Geochelone
Encyclopedia
Geochelone is a genus
of tortoise
s.
Geochelone tortoises, which are also known as typical tortoises or terrestrial turtles, can be found in Africa
and Asia
. They primarily eat plant
s.
The genus consists of three extant species:
A number of tortoise species have been recently removed from the genus. This taxon as fornerly defined was "polyphyletic, representing at least four independent clade
s". Tortoises removed include members of Aldabrachelys
(from the Seychelles
and Madagascar
), Astrochelys
(Madagascar), Chelonoidis
(South America
and the Galápagos Islands
), Stigmochelys (Africa) and earlier, the extinct
genus Colossochelys (southern Asia).
, allowing it to turn over when lying upside down very easily.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of tortoise
Tortoise
Tortoises are a family of land-dwelling reptiles of the order of turtles . Like their marine cousins, the sea turtles, tortoises are shielded from predators by a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The tortoise...
s.
Geochelone tortoises, which are also known as typical tortoises or terrestrial turtles, can be found in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. They primarily eat plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s.
The genus consists of three extant species:
- Indian star tortoiseIndian Star TortoiseThe Indian star tortoise is a species of tortoise found in dry areas and scrub forest in India and Sri Lanka. This species is quite popular in the exotic pet trade.-Anatomy and morphology:...
(G. elegans) - Burmese star tortoiseBurmese Star TortoiseThe Burmese star tortoise is becoming extinct in its native Myanmar . It lives in the dry, deciduous forest, and is eaten both by the native Burmese, and is traded to the Chinese, where it is sometimes found in the food markets. It is on CITES Appendix II, meaning a permit from the country of...
(G. platynota) - African spurred tortoiseAfrican Spurred TortoiseThe African spurred tortoise , also called the African spur thigh tortoise or the sulcata tortoise, is a species of tortoise which inhabits the southern edge of the Sahara desert, in northern Africa...
(G. sulcata)
A number of tortoise species have been recently removed from the genus. This taxon as fornerly defined was "polyphyletic, representing at least four independent clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
s". Tortoises removed include members of Aldabrachelys
Aldabrachelys
Aldabrachelys is the currently recognised genus for the Seychelles and Madagascan radiations of giant tortoises, including the Aldabra giant tortoise...
(from the Seychelles
Seychelles
Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar....
and Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
), Astrochelys
Astrochelys
Astrochelys is a genus of tortoises in the family Testudinidae. There are two species, both found in Madagascar and both classified as Critically Endangered on the IUCN Red List.- Species :...
(Madagascar), Chelonoidis
Chelonoidis
Chelonoidis is a genus of turtles in the tortoise family. They are found in South America and the Galápagos Islands. They were formerly assigned to Geochelone, but a recent comparative genetic analysis has indicated that they are actually most closely related to African hingeback tortoises. Their...
(South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
and the Galápagos Islands
Galápagos Islands
The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
), Stigmochelys (Africa) and earlier, the extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
genus Colossochelys (southern Asia).
"Self-righting" shell
The form of the shell of the Indian star tortoise (Geochelone elegans) resembles a gömböcGömböc
A gömböc is a convex three-dimensional homogeneous body which, when resting on a flat surface, has just one stable and one unstable point of equilibrium. Its existence was conjectured by Russian mathematician Vladimir Arnold in 1995 and proven in 2006 by Hungarian scientists Gábor Domokos and Péter...
, allowing it to turn over when lying upside down very easily.