''Tupinambis'' is a

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

which belongs to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Teiidae Teiidae is a family of lacertoidean lizards native to the Americas. Members of this family are generally known as whiptails or racerunners; however, tegus also belong to this family. Teiidae is sister to the Gymnophthalmidae, Gymnopthalmidae, and ...

and contains eight described

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. These large lizards are commonly referred to as tegus (''teiús'' in Portuguese). '' T. merianae'' (Argentine black and white tegu), '' T. rufescens'' (red tegu), and '' T. teguixin'' (gold tegu) are popular in the pet trade. They are primarily found in South America, although ''T. teguixin'' also occurs in

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

. In 2012, a number of tegu species were reclassified from ''Tupinambis'' to the previously used genus '' Salvator''. The newly proposed classification comes from a restructuring of the family Teiidae based upon the study of 137 morphological characteristics. The new classification is as follows: ''Salvator duseni'' (yellow tegu), ''Salvator rufescens'' (red tegu), ''Salvator merianae'' (Argentine black and white tegu), ''Tupinambis teguixin'' (gold tegu), ''Tupinambis longilineus'' (Rhondonia tegu), ''Tupinambis palustris'' (swamp tegu) and ''Tupinambis quadrilineatus'' (four-lined tegu).

Names

''Tupinambis'' lizards are called teiú in Portuguese. The lizards are also called tishiriú in the extinct Tuxá language of

Bahia Bahia () is one of the 26 Federative units of Brazil, states of Brazil, located in the Northeast Region, Brazil, Northeast Region of the country. It is the fourth-largest Brazilian state by population (after São Paulo (state), São Paulo, Mina ...

, Brazil,Pompeu Sobrinho, Thomaz. 1958. ''Línguas Tapuias desconhecidas do Nordeste: Alguns vocabulários inéditos''. Boletim de Antropologia (Fortaleza-Ceará) 2. 3-19. and dzižuảsu in the extinct Potiguara language of

Pernambuco Pernambuco ( , , ) is a States of Brazil, state of Brazil located in the Northeast Region, Brazil, Northeast region of the country. With an estimated population of 9.5 million people as of 2024, it is the List of Brazilian states by population, ...

, Brazil. As with many other animals from tropical South America (e.g. the Cariamae), ''Tupinambis'' owes its scientific name to the pioneering accounts given by Piso & Marcgrave in their ''

Historia Naturalis Brasiliae ''Historia Naturalis Brasiliae'' (), originally written in Latin, is the first scientific work on the natural history of Brazil, written by Dutch people, Dutch naturalist Willem Piso and containing research done by the German scientist Georg Ma ...

'' (1648). However, a misinterpretation (by

Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

) of the Latin text occurred, which reads "TEIVGVACV ..Tupinambis", 'to the Tupinambá ndigenous groupTEIVGVACU'. ''Tupinambis'' was merely a metalinguistic term meaning 'to/for the Tupinambá,' whereas the intended, indigenous name for the animal was ''teiú-guaçú'' izard-big lit. 'big lizard'.

Description

The ''Tupinambis'' species have

heterodont In anatomy, a heterodont (from Greek, meaning 'different teeth') is an animal which possesses more than a single tooth morphology. Human dentition is heterodont and diphyodont as an example. In vertebrates, heterodont pertains to animals wher ...

dentition consisting of four different types of teeth. Incisor-type—tricuspid—teeth reside at the tip of the mouth. Recurved canine-type teeth occur further back on the tooth row. Behind those reside a separate set of incisor-like teeth (though flattened in a perpendicular plane to the first set of incisors). The rearmost teeth are blunt, rounded, peg-shaped teeth. The rearmost two tooth classes only occur in sexually mature individuals, thus indicating an

ontogenetic Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the stu ...

shift in tooth morphology. Along with changes in tooth type, the frequency of each tooth type also changes with ontogeny, without an overall change in tooth count (approximately 70 teeth). Rather than increase tooth count, the teeth themselves increase in size as the jaw grows from hatchling to adult. This ontogenetic shift in tooth morphology suggests a shift in diet with age; however, few dietary studies have been done to support this claim and limited stomach content observations do not show much variability between hatchlings and juveniles. ''T. teguxin'' is an omnivore, consuming both fruit and as well as invertebrate and vertebrate prey.

Taxonomy

Species listed alphabetically by specific name.

Evolution

Mitochondrial DNA analysis indicates a deep divergence between a northern clade (containing ''T. teguixin'', ''T. palustris'' and ''T. quadrilineatus'') and a southern clade (containing ''T. duseni''). The northern and southern clades are morphologically distinct, with the northern clade possessing a single pair of loreal scales between the eye and the nostril and a smooth texture to the scales on the body and the southern clade possessing two pairs of loreal scales and a bumpy texture to the scales on the body. At least one review of the morphology of the family Teiidae has placed the tegus of the southern clade in the genus '' Salvator.'' Subsequent studies support the paraphyletic status of ''Tupinambis'', though further research will be necessary to determine if the split will gain wider acceptance among the herpetological community. Comparative analysis of hemipenial anatomy also provides support for the split between ''Tupinambis'' and ''Salvator''. Tegus probably originated sometime during the Cenozoic era. ''Tupinambis'' fossils from Argentina date back to the Late

Miocene The Miocene ( ) is the first epoch (geology), 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 mea ...

. Fossils of the extinct tegu ''Paradracaena'' can be found in earlier Miocene deposits.

Names

Description

Taxonomy

Evolution

References

Further reading