''Chelonoidis'' is a genus of turtles in the

tortoise Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like ot ...

family erected by

Leopold Fitzinger Leopold Joseph Franz Johann Fitzinger (13 April 1802 – 20 September 1884) was an Austrian zoologist. Fitzinger was born in Vienna and studied botany at the University of Vienna under Nikolaus Joseph von Jacquin. He worked at the Vienna Naturhi ...

in 1835. They are found in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the souther ...

and the

Galápagos Islands The Galápagos Islands ( es, Islas Galápagos) are an archipelago of volcanic islands in the Eastern Pacific, located around the Equator west of the mainland of South America. They form the Galápagos Province of the Republic of Ecuador, with ...

, and formerly had a wide distribution in the

West Indies The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Great ...

. The multiple subspecies of the

Galápagos tortoise The Galápagos tortoise or Galápagos giant tortoise (''Chelonoidis niger'') is a species of very large tortoise in the genus ''Chelonoidis'' (which also contains three smaller species from mainland South America). It comprises 15 subspecies (13 ...

are among the largest

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

terrestrial chelonians. Giant members of the genus, such as Lutz's giant tortoise (''C. lutzae'') were also present in mainland South America and the West Indies during the

Pleistocene The Pleistocene ( , often referred to as the '' Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed ...

Taxonomy

They were formerly assigned to ''

Geochelone ''Geochelone'' is a genus of tortoises. ''Geochelone'' tortoises, which are also known as typical tortoises or terrestrial turtles, can be found in southern Asia. They primarily eat plants. Species The genus consists of two extant species: A n ...

'', but a 2006 genetic analysis indicated that they were actually most closely related to hingeback tortoises. However, a more recent genetic analysis of

mtDNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondrion, mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mit ...

has found that they are actually most closely related to the lineage containing ''

Centrochelys ''Centrochelys'' is a genus of tortoise. It contains one extant species and several extinct species: * ''Centrochelys atlantica'' * '' Centrochelys burchardi'' * ''Centrochelys marocana'' * ''Centrochelys robusta'' * ''Centrochelys vulcanica'' * ...

'' and ''

''. Their ancestors apparently floated across the

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...

from

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

in the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

. This crossing was made possible by their ability to float with their heads up and to survive up to six months without food or water. Based on

analysis, the extant ''Chelonoidis'' members can be divided into two lineages, with one containing the

red-footed tortoise The red-footed tortoise (''Chelonoidis carbonarius'') is a species of tortoise from northern South America. These medium-sized tortoises generally average as adults, but can reach over . They have dark-colored, loaf-shaped carapaces (back shell ...

(''C. carbonarius'') and

yellow-footed tortoise The yellow-footed tortoise (''Chelonoidis denticulatus''), also known as the Brazilian giant tortoise, commonly referred to as the Brazilian giant turtle, or more commonly, the big turtle, is a species of tortoise in the family Testudinidae and ...

(''C. denticulatus''), and the other containing the Chaco tortoise (''C. chilensis'') and the Galapagos tortoises (''C. niger''). The now-extinct West Indian radiation is thought to group with the Chaco and Galapagos tortoises but is significantly

basal Basal or basilar is a term meaning ''base'', ''bottom'', or ''minimum''. Science * Basal (anatomy), an anatomical term of location for features associated with the base of an organism or structure * Basal (medicine), a minimal level that is nec ...

to both, and was a rather evolutionary distinct lineage, having diverged well before any of the modern species in the genus did and only 7 mya after the divergence of ''Chelonoidis'' from African tortoises. A 2021 study found that the extent of divergence among the species in the Galápagos and Bahamian ''Chelonoidis'' radiations may have been overestimated, and supported subsuming many of the species in both complexes to being subspecies of two parent species; '' C. alburyorum'' for the

Bahamas The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to 88% of the archi ...

and

Turks and Caicos Islands The Turks and Caicos Islands (abbreviated TCI; and ) are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of tropical islands in the Lucayan Archipelago of the Atlantic Ocean and ...

, and '' C. niger'' for the Galápagos. This was followed by the

Turtle Taxonomy Working Group The Turtle Taxonomy Working Group (TTWG) is an informal working group of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group (TFTSG). It is composed of a number of leading turtle taxonomist In biology, taxonomy () is the scientific s ...

and the

Reptile Database The Reptile Database is a scientific database that collects taxonomic information on all living reptile species (i.e. no fossil species such as dinosaurs). The database focuses on species (as opposed to higher ranks such as families) and has entri ...

in 2021. The names of several species names in the genus have often been misspelled, beginning in the 1980s when ''Chelonoidis'' was elevated to genus and mistakenly treated as feminine, an error recognized and fixed in 2017.

Distribution

Presently, ''Chelonoidis'' are distributed throughout most of

, as well as most of the Galápagos; the genus extended north into

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

during the

and most of the

up to the late

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togeth ...

. ''C. carbonarius'' and ''C. denticulatus'' are presently found on some of the

Lesser Antillean The Lesser Antilles ( es, link=no, Antillas Menores; french: link=no, Petites Antilles; pap, Antias Menor; nl, Kleine Antillen) are a group of islands in the Caribbean Sea. Most of them are part of a long, partially volcanic island arc be ...

islands, but the provenance of these individuals is unknown, and they could have been introduced by

Amerindians The Indigenous peoples of the Americas are the inhabitants of the Americas before the arrival of the European settlers in the 15th century, and the ethnic groups who now identify themselves with those peoples. Many Indigenous peoples of the A ...

during

pre-Columbian In the history of the Americas, the pre-Columbian era spans from the original settlement of North and South America in the Upper Paleolithic period through European colonization, which began with Christopher Columbus's voyage of 1492. Usually, ...

times.

In the West Indies

In prehistoric times, a large insular radiation of giant ''Chelonoidis'' existed on many West Indian islands, including the

Greater Antilles The Greater Antilles ( es, Grandes Antillas or Antillas Mayores; french: Grandes Antilles; ht, Gwo Zantiy; jam, Grieta hAntiliiz) is a grouping of the larger islands in the Caribbean Sea, including Cuba, Hispaniola, Puerto Rico, Jamaica, ...

and Lesser Antilles. While some such as those on

Curaçao Curaçao ( ; ; pap, Kòrsou, ), officially the Country of Curaçao ( nl, Land Curaçao; pap, Pais Kòrsou), is a Lesser Antilles island country in the southern Caribbean Sea and the Dutch Caribbean region, about north of the Venezuela coas ...

Anguilla Anguilla ( ) is a British Overseas Territory in the Caribbean. It is one of the most northerly of the Leeward Islands in the Lesser Antilles, lying east of Puerto Rico and the Virgin Islands and directly north of Saint Martin. The territ ...

, and

Barbados Barbados is an island country in the Lesser Antilles of the West Indies, in the Caribbean region of the Americas, and the most easterly of the Caribbean Islands. It occupies an area of and has a population of about 287,000 (2019 estimate ...

are thought to have gone extinct during the

Late Pleistocene The Late Pleistocene is an unofficial age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch within ...

, other species such as those on the Greater Antilles and the Bahamas are thought to have been driven to extinction after the first

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

s arrived on the islands, from

7000 BC The 7th millennium BC spanned the years 7000 BC to 6001 BC (c. 9 ka to c. 8 ka). It is impossible to precisely date events around this millennium, and all dates mentioned here are estimates mostly based on geological and anthropological analysi ...

onwards. The

Bahamian tortoise ''Chelonoidis alburyorum'' is an extinct species of land tortoise that lived from the late Pleistocene to around 1400 CE. The species was discovered and described by Richard Franz and Shelley E. Franz, the findings being published in 2009. Name ...

(''C. alburyorum'') was one of the last-surviving of these species, persisting up to 1170 AD on the Abacos, up to 1200 AD on Grand Turk, and up to 1400 AD on the

Middle Caicos Middle Caicos is the largest island in the Turks and Caicos Islands The Turks and Caicos Islands (abbreviated TCI; and ) are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of t ...

, just under a century prior to European colonization of the islands.Turtle Extinctions Working Group (Rhodin, A.G.J., Thomson, S., Georgalis, G., Karl, H.-V., Danilov, I.G., Takahashi, A., de la Fuente, M.S., Bourque, J.R., Delfino, M., Bour, R., Iverson, J.B., Shaffer, H.B., and van Dijk, P.P.). 2015
Turtles and tortoises of the world during the rise and global spread of humanity: first checklist and review of extinct Pleistocene and Holocene chelonians.
Chelonian Research Monographs 5(8) A 2017 study found that some of these species such as those from

Hispaniola Hispaniola (, also ; es, La Española; Latin and french: Hispaniola; ht, Ispayola; tnq, Ayiti or Quisqueya) is an island in the Caribbean that is part of the Greater Antilles. Hispaniola is the most populous island in the West Indies, and t ...

were specialists adapted to dry, open habitats such as

Hispaniolan dry forests The Hispaniolan dry forests are a tropical dry broadleaf forest ecoregion on the island of Hispaniola (split between the Dominican Republic and Haiti). They cover , around 20% of the island's area. Geography The dry forests are found mostly on ...

and had a major role in shaping them; following a decrease in the extent of these ecosystems after the end of the

, these tortoises were restricted to refugia habitats up until their extinction. A 2021 study identified two distinct genetic lineages within the Bahaman tortoise, ''C. alburyorum'', but also sometimes found the remains of members of both lineages on the same island, even though the lineages would have only separated with geographic isolation. This indicates that the early inhabitants of the West Indies were successfully transporting the large tortoises across islands, presumably for the purpose of consumption, and thus causing the remains geographically-isolated lineages to co-occur on the same islands.

''Chelonoidis'' species

Note that the genus name ''Chelonoidis'' is masculine under the rules of the

ICZN The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the Int ...

, and adjectival species names must agree in gender; the species names below are displayed in keeping with this rule, and may differ from how they commonly appear in publications.

Extant and recently extinct species

Listed alphabetically: *'' C. carbonarius'' –

*'' C. chilensis'' – Chaco tortoise *'' C. denticulatus'' –

*'' C. niger'' –

– with the following subspecies: ** '' C. n. abingdonii'' – Pinta Island tortoise (extinct as of 2012, but could be bred back from hybrids and/or persist as lone individuals) ** '' C. n. becki'' –

Volcán Wolf giant tortoise The Volcán Wolf giant tortoise (''Chelonoidis niger becki)'', also known commonly as the Wolf Volcano giant tortoise and the Cape Berkeley giant tortoise, is a subspecies of Galápagos tortoise in the family Testudinidae. The subspecies is nat ...

** '' C. n. chathamensis'' – San Cristobal giant tortoise ** '' C. n. darwini'' –

Santiago Island giant tortoise The Santiago Island giant tortoise (''Chelonoidis niger darwini)'', also known commonly as the Santiago giant tortoise and the James Island tortoise, is a subspecies of Galápagos tortoise in the family Testudinidae. The subspecies is endemi ...

** '' C. n. donfaustoi'' – eastern Santa Cruz tortoise ** '' C. n. duncanensis'' – Pinzon Island giant tortoise ** '' C. n. guntheri '' –

Sierra Negra giant tortoise ''Chelonoidis niger guentheri'', commonly known as the Sierra Negra giant tortoise or Günther's giant tortoise, is a subspecies of Galápagos tortoise endemic to the Galápagos archipelago in the eastern Pacific Ocean. The specific epithet ''g ...

** '' C. n. hoodensis'' –

Hood Island giant tortoise The Hood Island giant tortoise (''Chelonoidis niger hoodensis'') is a subspecies of Galápagos tortoise endemic to Española Island in the Galápagos. Population history This population was very heavily exploited by whalers in the 19th century ...

** '' C. n. microphyes '' –

Volcán Darwin giant tortoise ''Chelonoidis niger microphyes'', also known as the Volcán Darwin giant tortoise, Darwin Volcano giant tortoise or Tagus Cove giant tortoise, is a subspecies of Galápagos tortoise endemic to the Galápagos archipelago in the equatorial east ...

** '' C. n. niger'' –

Floreana giant tortoise The Floreana giant tortoise (''Chelonoidis niger niger''), also known as the Charles Island giant tortoise, is an extinct subspecies of the Galápagos tortoise endemic to the Galápagos archipelago in the equatorial eastern Pacific Ocean. T ...

(driven to extinction in the mid-19th century, but could be bred back from hybrids) ** '' C. n. phantasticus'' –

Fernandina Island tortoise Fernandina may refer to: *Fernandina Beach, Florida **Original Town of Fernandina Historic Site * Fernandina Island, Galapagos Islands *Fernandina (fruit) The Florentine citron – citron hybrid of Florence ( it, cedrato di Firenze) – is a ve ...

(rediscovered in February 2019) ** '' C. n. porteri'' –

western Santa Cruz tortoise The western Santa Cruz tortoise (''Chelonoidis niger porteri'') is a subspecies of Galápagos tortoise endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country ...

** ''C.'' ''n.'' 'Santa Fe Island lineage' –

Santa Fe Island tortoise The Santa Fe Island tortoise (''Chelonoidis'' ''niger'' ssp.), also known as the Santa Fe tortoise or Santa Fe giant tortoise, is an undescribed extinct taxon of Galápagos tortoise endemic to Santa Fe Island in the Galápagos archipelago in th ...

( undescribed, driven to extinction in the mid-19th century) ** '' C. n. vandenburghi'' –

Volcán Alcedo giant tortoise ''Chelonoidis niger vandenburghi'', also known as the Volcán Alcedo giant tortoise, the Alcedo Volcano giant tortoise or the Alcedo giant tortoise, is a subspecies of Galápagos tortoise endemic to the Galápagos archipelago in the equatoria ...

** '' C. n. vicina'' –

Cerro Azul giant tortoise ''Chelonoidis niger vicina'', commonly known as the Cerro Azul giant tortoise, Iguana Cove tortoise or the Isabela Island giant tortoise, is a subspecies of Galápagos tortoise endemic to Isabela Island (Galápagos), Isabela Island in the Galápa ...

* '' C. alburyorum'' –

(Late

The Bahamas The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to 88% of the arc ...

and

Turks & Caicos Islands The Turks and Caicos Islands (abbreviated TCI; and ) are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of tropical islands in the Lucayan Archipelago of the Atlantic Ocean and ...

) * '' C. cubensis'' – Cuban giant tortoise (Early Holocene of

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...

) * '' C. dominicensis'' (

Plio-Pleistocene The Plio-Pleistocene is an informally described geological pseudo-period, which begins about 5 million years ago (Mya) and, drawing forward, combines the time ranges of the formally defined Pliocene and Pleistocene epochs—marking from about 5& ...

to early Holocene of the

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares with ...

) * '' C. monensis'' – Mona tortoise (Late Holocene of

Isla de Mona Mona ( es, Isla de Mona) is the third-largest island of the Puerto Rican archipelago, after the main island of Puerto Rico and Vieques. It is the largest of three islands in the Mona Passage, a strait between the Dominican Republic and Puerto ...

Puerto Rico Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...

) Relationships of the family, after Kehlmaier et al, 2017 and 2021.

Fossil species

Late Quaternary fossil species

Listed alphabetically: * '' C. lutzae –'' Lutz’s giant tortoise (

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

) * '' C. marcanoi'' ( Quaternary of the Dominican Republic) (''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...

'' as

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

does not allow for distinguishing between species) * '' C. sombrerensis'' –

Sombrero giant tortoise A sombrero (Spanish , ) is a type of wide-brimmed Mexican men's hat used to shield the face and eyes from the sun. It usually has a high pointed crown, an extra-wide brim (broad enough to cast a shadow over the head, neck and shoulders of the w ...

(Late Pleistocene of

Sombrero A sombrero (Spanish , ) is a type of wide-brimmed Mexican men's hat used to shield the face and eyes from the sun. It usually has a high pointed crown, an extra-wide brim (broad enough to cast a shadow over the head, neck and shoulders of the w ...

)

Other fossil species

Listed alphabetically: * '' C. australis'' (

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ...

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58C. gallardoi'' (Miocene of Argentina, Late Pleistocene of

Ecuador Ecuador ( ; ; Quechuan languages, Quechua: ''Ikwayur''; Shuar language, Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechuan ...

) * † '' C. gringorum'' (Miocene of Argentina) * † '' C. hesternus'' (Miocene of Colombia)

References

{{Taxonbar, from=Q2080003 Turtle genera Taxa named by Leopold Fitzinger