| Tupinambis | |
|---|---|
 | |
| Gold tegu (Tupinambis teguixin) | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Suborder: | Lacertoidea |
| Family: | Teiidae |
| Genus: | Tupinambis Daudin, 1802 |
| Type species | |
| Tupinambis monitor Daudin 1802 | |
Tupinambis is alizardgenus which belongs to thefamilyTeiidae and contains eight describedspecies. These large lizards are commonly referred to astegus. They are primarily found in South America, althoughT. teguixin also occurs inPanama.
In 2012, a number of tegu species were reclassified fromTupinambis to the previously used genusSalvator. 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) andTupinambis quadrilineatus (four-lined tegu).[1]
Tupinambis lizards are calledteiú in Portuguese. The lizards are also calledtishiriú in the extinctTuxá language ofBahia, Brazil,[2] anddzižuảsu in the extinctPotiguara language ofPernambuco, Brazil.[3]
As with many other animals from tropical South America (e.g. theCariamae),Tupinambis owes its scientific name to the pioneering accounts given by Piso & Marcgrave in theirHistoria Naturalis Brasiliae (1648). However, a misinterpretation (byLinnaeus) of the Latin text occurred, which reads "TEIVGVACV [...] Tupinambis", 'to the Tupinambá [Indigenous group] TEIVGVACU'.Tupinambis was merely a metalinguistic term meaning 'to/for the Tupinambá,' whereas the intended, indigenous name for the animal wasteiú-guaçú [lizard-big]; lit. 'big lizard'.[4]
TheTupinambis species haveheterodont dentition consisting of four different types of teeth.[5] Incisor-type—tricuspid—teeth reside at the tip of the mouth.[5] Recurved canine-type teeth occur further back on the tooth row.[5] Behind those reside a separate set of incisor-like teeth (though flattened in a perpendicular plane to the first set of incisors).[5] The rearmost teeth are blunt, rounded, peg-shaped teeth.[5] The rearmost two tooth classes only occur in sexually mature individuals, thus indicating anontogenetic shift in tooth morphology.[5] 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).[5] Rather than increase tooth count, the teeth themselves increase in size as the jaw grows from hatchling to adult.[5] 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.[5]T. teguxin is an omnivore, consuming both fruit and as well as invertebrate and vertebrate prey.[6]
Species listed alphabetically byspecific name.[7]
| Species | Common name | Image |
|---|---|---|
| Tupinambis cryptus Murphy, Jowers, Lehtinen, Charles, Colli, Peres Jr., Hendry, & Pyron, 2016 | cryptic golden tegu |  |
| Tupinambis cuzcoensis Murphy, Jowers, Lehtinen, Charles, Colli, Peres Jr., Hendry, & Pyron, 2016 | Cusco tegu | _(cropped).jpg) |
| Tupinambis longilineus Ávila-Pires, 1995 | Rondonia tegu | |
| Tupinambis matipu Silva, Ribeiro-Junior, & Ávila-Pires, 2018[8] | _1.jpg) | |
| Tupinambis palustris | swamp tegu | |
| Tupinambis quadrilineatus Manzani & Abe, 1997 | four-lined tegu | .jpg) |
| Tupinambis teguixin | gold tegu | _(20123669353).jpg) |
| Tupinambis zuliensis Murphy, Jowers, Lehtinen, Charles, Colli, Peres Jr., Hendry, & Pyron, 2016 | Maracaibo Basin tegu |
Mitochondrial DNA analysis indicates a deep divergence between a northern clade (containingT. teguixin,T. palustris andT. quadrilineatus) and a southern clade (containingT. duseni).[10] The northern and southern clades are morphologically distinct, with the northern clade possessing a single pair ofloreal 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.[11] At least one review of the morphology of the family Teiidae has placed the tegus of the southern clade in the genusSalvator.[12] Subsequent studies support the paraphyletic status ofTupinambis, though further research will be necessary to determine if the split will gain wider acceptance among the herpetological community.[13] Comparative analysis ofhemipenial anatomy also provides support for the split betweenTupinambis andSalvator.[14]
Tegus probably originated sometime during the Cenozoic era.Tupinambis fossils from Argentina date back to theLate Miocene,[15] and further remains are also known from the Pleistocene of northwestern Argentina.[16] Fossils of the extinct teguParadracaena can be found in earlier Miocene deposits.[17]