{{Short description|Family of lizards}} {{Automatic taxobox | name = Iguanids | image = AA_Iguana_Fot_Ars_Summum.JPG | taxon = Iguanidae | authority = Oppel, 1811 | subdivision_ranks = Genera | subdivision = ''Amblyrhynchus''<br /> ''Brachylophus''<br /> ''Cachryx''<br /> ''Conolophus''<br /> ''Ctenosaura''<br /> ''Cyclura''<br /> ''Dipsosaurus''<br /> ''Iguana''<br /> ''Sauromalus'' }}

The '''Iguanidae''' is a family of lizards composed of the iguanas, chuckwallas, and their prehistoric relatives,<ref name=EoR>{{cite book |editor1=Cogger, H.G. |editor2=Zweifel, R.G.|author=Bauer, Aaron M.|year=1998|title=Encyclopedia of Reptiles and Amphibians|publisher= Academic Press|location=San Diego|pages= 140–142|isbn= 0-12-178560-2}}</ref> including the widespread green iguana.

== Taxonomy == Iguanidae is thought to be the sister group to the collared lizards (family Crotaphytidae). This family likely first appeared in Cenozoic, previously identified two Cretaceous genera (''Pristiguana'' and ''Pariguana'') are unlikely to belong to this family.<ref name=":2" /> The subfamily Iguaninae, which contains all modern genera, likely originated in the earliest Paleocene, about 62 million years ago. The most basal extant genus, ''Dipsosaurus,'' diverged from the rest of Iguaninae during the late Eocene, about 38 million years ago, with ''Brachylophus'' following a few million years later at about 35 million years ago, presumably after its dispersal event to the Pacific. All other modern iguana genera formed in the Neogene period.<ref name=":0">{{Cite journal|date=2017-10-01|title=Never judge an iguana by its spines: Systematics of the Yucatan spiny tailed iguana, Ctenosaura defensor (Cope, 1866)|url=https://www.sciencedirect.com/science/article/abs/pii/S1055790317305201|journal=Molecular Phylogenetics and Evolution|language=en|volume=115|pages=27–39|doi=10.1016/j.ympev.2017.07.010|issn=1055-7903|last1=Malone|first1=Catherine L.|last2=Reynoso|first2=Víctor Hugo|last3=Buckley|first3=Larry|pmid=28716742|bibcode=2017MolPE.115...27M |url-access=subscription}}</ref>

A phylogenetic tree of Iguaninae is shown here:<ref name=":0" /> {{Clade|{{clade |1=''Dipsosaurus'' |2={{clade |1=''Brachylophus'' |2={{clade |1=''Cyclura'' |2={{clade |1={{clade |1=''Ctenosaura'' |2={{clade |1=''Cachryx'' |2={{clade |1=''Amblyrhynchus'' |2=''Conolophus'' }} }} }} |2={{clade |1=''Iguana'' |2=''Sauromalus'' }} }} }} }} }}}}

== Description == Iguanas and iguana-type species are diverse in terms of size, appearance, and habitat. They typically flourish in tropical, warm climates, such as regions of South America and islands in the Caribbean and in the Pacific. Iguanas typically possess dorsal spines across their back, a dewlap on the neck, sharp claws, a long whip-like tail, and a stocky, squat build. Most iguanas are arboreal, living in trees, but some species tend to be more terrestrial, which means they prefer the ground. Iguanas are typically herbivores and their diets vary based on what plant life is available within their habitat. Iguanas across many species remain oviparious, and exhibit little to no parental care when their eggs hatch. They do, however, display nest-guarding behavior. Like all extant non-avian reptiles, they are poikilothermic, and also rely on regular periods of basking under the sun to thermoregulate.<ref name=":1">{{Cite web|title=Anoles, Iguanas, and Relatives: Iguanidae {{!}} Encyclopedia.com|url=https://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/anoles-iguanas-and-relatives-iguanidae#CAPE_SPINYTAIL_IGUANA_Ctenosaura_hemilopha_SPECIES_ACCOUNTS|access-date=2021-03-31|website=www.encyclopedia.com}}</ref>

==Distribution== All but one of the modern iguana genera are native to the Americas, ranging from the deserts of the Southwestern United States through Mexico, Central America, and the Caribbean, to throughout South America down to northernmost Argentina. Some iguanas like ''I. iguana'' have spread from their native regions of Central and South America into many Pacific Islands, and even to Fiji, Japan, and Hawaiʻi, due to the exotic pet trade and illegal introductions into the ecosystems.<ref name="bioone.org">{{Cite journal|last1=Falcón|first1=Wilfredo|last2=Ackerman|first2=James D.|last3=Recart|first3=Wilnelia|last4=Daehler|first4=Curtis C.|date=April 2013|title=Biology and Impacts of Pacific Island Invasive Species. 10. Iguana iguana, the Green Iguana (Squamata: Iguanidae)|url=http://www.bioone.org/doi/10.2984/67.2.2|journal=Pacific Science|language=en|volume=67|issue=2|pages=157–186|doi=10.2984/67.2.2|s2cid=84905657|issn=0030-8870|url-access=subscription}}</ref> Other iguanas, like the Galapagos pink iguana (''C. marthae'') are endemic only to specific regions on the Galapagos islands. The Grand Cayman blue iguana, ''C. lewisi'', is endemic only to the Grand Cayman island, limited to a small wildlife reserve.<ref name=":1" /> The only non-American iguana species are the members of the genus ''Brachylophus'' and the extinct ''Lapitiguana'', which are found on Fiji and formerly Tonga; their distribution is thought to be the result of the longest overwater dispersal event ever recorded for a vertebrate species, with them rafting over 8000&nbsp;km across the Pacific from the Americas to the Fiji and Tonga.<ref>{{Cite journal|last1=Keogh|first1=J. Scott|last2=Edwards|first2=Danielle L|last3=Fisher|first3=Robert N|last4=Harlow|first4=Peter S|date=2008-10-27|title=Molecular and morphological analysis of the critically endangered Fijian iguanas reveals cryptic diversity and a complex biogeographic history|journal=Philosophical Transactions of the Royal Society B: Biological Sciences|volume=363|issue=1508|pages=3413–3426|doi=10.1098/rstb.2008.0120|issn=0962-8436|pmc=2607380|pmid=18782726}}</ref>

==Extant genera== {| class="wikitable" |- ! Image !! Genus !! Species |- |175px || ''Amblyrhynchus'' {{small|Bell, 1825}} – marine iguana || *''Amblyrhynchus cristatus'' — Marine iguana <small>Bell, 1825</small> |- |175px || ''Brachylophus'' {{small|Cuvier, 1829}} – Fijian/Tongan iguanas|| * ''Brachylophus fasciatus'' — Lau banded iguana <small>(Brongniart, 1800)</small> * ''Brachylophus vitiensis'' — Fiji crested iguana <small>Gibbons, 1981</small> * ''Brachylophus bulabula'' — Fiji banded iguana <small>Keogh, Edwards, Fisher, & Harlow, 2008</small> * ''Brachylophus gau'' — Gau iguana <small>Fisher, 2017</small> |- |175px || ''Cachryx'' {{small|Cope, 1866}} – spinytail iguanas || * ''Cachryx alfredschmidti'' — Campeche spiny-tailed iguana <small>(Köhler, 1995)</small> * ''Cachryx defensor —'' Yucatán spiny-tailed iguana <small>(Cope, 1866)</small> |- |175px || ''Conolophus'' {{small|Fitzinger, 1843}} – Galápagos land iguanas|| * ''Conolophus pallidus'' ''—'' Barrington land iguana Heller, 1903 * ''Conolophus subcristatus —'' Galápagos land iguana <small>(Gray, 1831)</small> * ''Conolophus marthae —'' Galápagos pink land iguana <small>Gentile & Snell, 2009</small> |- |175px || ''Ctenosaura'' {{small|Wiegmann, 1828}} – spiny-tailed iguanas|| * ''Ctenosaura acanthura'' ''—'' Mexican spiny-tailed iguana <small>Shaw, 1802</small> * ''Ctenosaura alfredschmidti —'' Campeche spiny-tailed iguana <small>(Köhler, 1995)</small> * ''Ctenosaura bakeri'' ''—'' Baker's spiny-tailed iguana <small>Stejneger, 1901</small> * ''Ctenosaura clarki'' ''—'' Balsas spiny-tailed iguana <small>Bailey, 1928</small> * ''Ctenosaura conspicuosa'' ''—'' San Esteban spiny-tailed iguana <small>(Dickerson, 1919)</small> * ''Ctenosaura defensor'' ''—'' Yucatán spiny-tailed iguana <small>(Cope, 1866)</small> * ''Ctenosaura flavidorsalis'' Yellow-backed spiny-tailed iguana <small>Köhler & Klemmer, 1994</small> * ''Ctenosaura hemilopha'' ''—'' Baja California spiny-tailed iguana <small>(Cope, 1863)</small> * ''Ctenosaura macrolopha'' — Sonoran spiny-tailed iguana <small>Smith, 1972</small> * ''Ctenosaura melanosterna'' — Black-chested spiny-tailed iguana <small>Buckley & Axtell, 1997</small> * ''Ctenosaura nolascensis'' — Nolasco spiny-tailed iguana <small>Smith, 1972</small> * ''Ctenosaura oaxacana'' — Oaxacan spiny-tailed iguana <small>Köhler & Hasbun, 2001</small> * ''Ctenosaura oedirhina'' — Roatán spiny-tailed iguana <small>De Queiroz, 1987</small> * ''Ctenosaura palearis'' — Motagua spiny-tailed iguana <small>Stejneger, 1899</small> * ''Ctenosaura pectinata'' — Western spiny-tailed iguana <small>(Wiegmann, 1834)</small> * ''Ctenosaura quinquecarinata'' — Five-keeled spiny-tailed iguana <small>(Gray, 1842)</small> * ''Ctenosaura similis'' — Black spiny-tailed iguana <small>(Gray, 1831)</small> |- |175px || ''Cyclura'' {{small|Harlan, 1825}} – West Indian rock iguanas|| * ''Cyclura carinata'' — Turks and Caicos rock iguana <small>Harlan, 1825</small> ** ''Cyclura carinata bartschi'' — Bartsch's iguana <small>Cochran, 1931</small> * ''Cyclura collei'' — Jamaican iguana <small>Gray, 1845</small> * ''Cyclura cornuta'' — Rhinoceros iguana <small>(Bonnaterre, 1789)</small> ** †''Cyclura cornuta onchiopsis —'' Navassa Island iguana * ''Cyclura cychlura —'' Northern Bahamian Rock Iguana <small>(Cuvier, 1829)</small> ** ''Cyclura cychlura cychlura'' ''—'' Andros Island iguana <small>(Cuvier, 1829)</small> ** ''Cyclura cychlura figginsi'' ''—'' Exuma Island iguana <small>Barbour, 1923</small> ** ''Cyclura cychlura inornata'' ''—'' Allen Cays iguana <small>(Barbour & Noble, 1916)</small> * ''Cyclura lewisi'' ''—'' Blue iguana <small>(Grant, 1940)</small> * ''Cyclura nubila'' ''—'' Cuban iguana <small>(Gray, 1831)</small> ** Cyclura nubila caymanensis ''—'' Lesser Caymans iguana <small>(Barbour & Noble, 1916)</small> * ''Cyclura pinguis'' ''—'' Anegada ground iguana <small>Barbour, 1917</small> * ''Cyclura ricordii —'' Ricord's iguana <small>(Duméril & Bibron, 1837)</small> * ''Cyclura rileyi'' ''—'' San Salvador iguana <small>Stejneger, 1903</small> ** ''Cyclura rileyi'' ''rileyi —'' Central Bahamian Rock Iguana <small>Stejneger, 1903</small> ** ''Cyclura rileyi cristata'' ''—'' White Cay iguana <small>(Schmidt, 1920)</small> ** ''Cyclura rileyi nuchalis —'' Acklins iguana <small>Barbour and Noble, 1916</small> * ''Cyclura stejnegeri'' ''—'' Mona ground Iguana <small>Barbour and Noble, 1916</small> |- |175px || ''Dipsosaurus'' {{small|Hallowell, 1854}} – desert iguanas || *''Dipsosaurus dorsalis —'' Desert iguana <small>(Baird and Girard, 1852)</small> *''Dipsosaurus catalinensis —'' Catalina desert iguana <small>(Van Denburgh, 1922)</small> |- |175px || ''Iguana'' {{small|Laurenti, 1768}} – green and Lesser Antillean iguanas|| *''Iguana delicatissima —'' Lesser Antillean iguana <small>Laurenti, 1768</small> *''Iguana iguana —'' Green iguana <small>(Linnaeus, 1758)</small> **''Iguana iguana insularis —'' Grenadines horned iguana **''Iguana iguana melanoderma —'' Saban black iguana **''Iguana iguana sanctaluciae —'' St. Lucia Horned Iguana |- |175px || ''Sauromalus'' {{small|Dumeril, 1856}} – chuckwallas || *''Sauromalus ater —'' Common chuckwalla <small>Dumeril, 1856</small> *''Sauromalus hispidus —'' Angel Island chuckwalla <small>Stejneger, 1891</small> *''Sauromalus klauberi —'' Spotted chuckwalla <small>Shaw, 1941</small> *''Sauromalus slevini —'' Monserrat chuckwalla <small>Van Denburgh, 1922</small> *''Sauromalus varius —'' Pinto chuckwalla <small>Dickerson, 1919</small> |- |}

==Fossils== {| class="wikitable" |- ! Image !! Genus !! Species |- |175px || ''Armandisaurus'' {{small|Norell & de Queiroz, 1991}} || *{{extinct}} ''Armandisaurus explorator'' |- |175px || ''Lapitiguana'' {{small|Pregill & Worthy, 2003}} || *{{extinct}} ''Lapitiguana impensa'' |- |175px || ''Pumilia'' {{small|Norell 1989}} || * {{extinct}} ''Pumilia novaceki'' |- |} Cretaceous ''Pristiguana brasiliensis'' and ''Pariguana lancensis'' are later excluded from the family.<ref>{{Cite journal |last1=Daza |first1=Juan D. |last2=Abdala |first2=Virginia |last3=Arias |first3=J. Salvador |last4=García-López |first4=Daniel |last5=Ortiz |first5=Pablo |date=2012 |title=Cladistic Analysis of Iguania and a Fossil Lizard from the Late Pliocene of Northwestern Argentina |journal=Journal of Herpetology |volume=46 |issue=1 |pages=104–119 |doi=10.1670/10-112 |hdl=11336/61054 |issn=0022-1511|hdl-access=free }}</ref><ref name=":2">{{Cite journal |last1=DeMar |first1=David G. |last2=Conrad |first2=Jack L. |last3=Head |first3=Jason J. |last4=Varricchio |first4=David J. |last5=Wilson |first5=Gregory P. |date=2017-01-25 |title=A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania) |journal=Proceedings of the Royal Society B: Biological Sciences |volume=284 |issue=1847 |article-number=20161902 |doi=10.1098/rspb.2016.1902 |pmc=5310030 |pmid=28123087}}</ref>

==Classification== Several classification schemes have been used to define the structure of this family. The "historical" classification recognized all New World iguanians, plus ''Brachylophus'' and the Madagascar oplurines, as informal groups and not as formal subfamilies.<ref name=EstesLizards>{{cite book |editor1=Estes, R. |editor2=Pregill, G.|author1=Etheridge, Richard |author2=de Queiroz, Kevin|year=1988|title=Phylogenetic Relationships of the Lizard Families, Essays Commemorating Charles L. Camp.|publisher= Stanford University Press|location=Stanford, California|pages= 283–368|isbn= 0-8047-1435-5}}</ref>

Frost and Etheridge (1989) formally recognized these informal groupings as families.<ref>D.R. Frost & R. Etheridge (1989) «A phylogenetic analysis and taxonomy of iguanian lizards (Reptilia: Squamata)» ''Univ. Kansas Mus. Nat. Hist. Misc. Publ.'' 81</ref><ref>D.R. Frost, R. Etheridge, D. Janies & T.A. Titus (2001) [http://research.amnh.org/scicomp/pdfs/Frost_etal2001b.pdf Total evidence, sequence alignment, evolution of polychrotid lizards, and a reclassification of the Iguania (Squamata: Iguania)] ''American Museum Novitates'' 3343: 38 pp.</ref>

Macey et al. (1997), in their analysis of molecular data for iguanian lizards recovered a monophyletic Iguanidae and formally recognized the eight families proposed by Frost and Etheridge (1989) as subfamilies of Iguanidae.<ref>{{cite journal | author = Macey J.R., Larson A., Ananjeva N.B., Papenfuss T.J. | year = 1997 | title = [Evolutionary shifts in three major structural features of the mitochondrial genome among iguanian lizards.] | journal = Journal of Molecular Evolution | volume = 44 | issue = 6| pages = 660–674 | doi = 10.1007/pl00006190 | pmid = 9169559 | bibcode = 1997JMolE..44..660M | s2cid = 30106562 }}</ref>

Schulte et al. (2003) reanalyzed the morphological data of Frost and Etheridge in combination with molecular data for all major groups of Iguanidae and recovered a monophyletic Iguanidae, but the subfamilies Polychrotinae and Tropidurinae were not monophyletic.<ref>{{cite journal | author = Schulte II J.A., Valladares J.P., Larson A. | year = 2003 | title = [Phylogenetic relationships within Iguanidae inferred using molecular and morphological data and a phylogenetic taxonomy of iguanian lizards.] | journal = Herpetologica | volume = 59 | issue = 3| pages = 399–419 | doi = 10.1655/02-48 | s2cid = 56054202 }}</ref>

Townsend et al. (2011), Wiens et al. (2012) and Pyron et al. (2013), in the most comprehensive phylogenies published to date, recognized most groups at family level, resulting in a narrower definition of Iguanidae.<ref name=Townsend2011>{{cite journal| author1=Townsend | author2=Mulcahy | author3=Noonan | author4=Sites Jr | author5=Kuczynski | author6=Wiens | author7=Reeder | year=2011 | title=Phylogeny of iguanian lizards inferred from 29 nuclear loci, and a comparison of concatenated and species-tree approaches for an ancient, rapid radiation | journal=Molecular Phylogenetics and Evolution | volume=61 | issue=2 | pages=363–380 | doi=10.1016/j.ympev.2011.07.008 | pmid=21787873 | bibcode=2011MolPE..61..363T }}</ref><ref name=Wiens2012>{{cite journal| author1=Wiens | author2=Hutter | author3=Mulcahy | author4=Noonan | author5=Townsend | author6=Sites Jr. | author7=Reeder | year=2012 | title=Resolving the phylogeny of lizards and snakes (Squamata) with extensive sampling of genes and species | journal=Biology Letters | volume=8 | issue=6 | pages=1043–1046 | doi=10.1098/rsbl.2012.0703 | pmid=22993238 | pmc=3497141 }}</ref><ref name=Pyron2013>{{cite journal| author1=Pyron | author2=Burbrink | author3=Wiens | year=2013 | title=A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes | journal=BMC Evolutionary Biology | volume=13 | issue=1 | page=93 | doi=10.1186/1471-2148-13-93 | pmid=23627680 | pmc=3682911 | doi-access=free | bibcode=2013BMCEE..13...93P }}</ref>

===Historical classification=== '''Family Iguanidae''' *Informal grouping anoloids: anoles, leiosaurs, ''Polychrus'' *Informal grouping basiliscines: casquehead lizards *Informal grouping crotaphytines: collared and leopard lizards *Informal grouping iguanines: marine, Fijian, Galapagos land, spinytail, rock, desert, green, and chuckwalla iguanas *Informal grouping morunasaurs: wood lizards, clubtails *Informal grouping oplurines: Madagascan iguanids *Informal grouping sceloporines: earless, spiny, tree, side-blotched and horned lizards *Informal grouping tropidurines: curly-tailed lizards, South American swifts, neotropical ground lizards

===Frost et al. (1989) classification of iguanas=== '''Family Corytophanidae'''<br/> '''Family Crotaphytidae'''<br/> '''Family Hoplocercidae'''<br/> '''Family Iguanidae''' *Genus ''Amblyrhynchus'' – marine iguana *Genus ''Brachylophus'' – Fijian/Tongan iguanas *Genus ''Cachryx'' – spinytail iguanas *Genus ''Conolophus'' – Galápagos land iguanas *Genus ''Ctenosaura'' – spinytail iguanas *Genus ''Cyclura'' – West Indian rock iguanas *Genus ''Dipsosaurus'' – desert iguana *Genus ''Iguana'' – green and Lesser Antillean iguanas *Genus ''Sauromalus'' – chuckwallas *Genus ''Armandisaurus'' (extinct chuckwalla) *Genus ''Lapitiguana'' (extinct giant Fijian iguana) *Genus ''Pumilia'' (extinct Palm Springs iguana) *Genus ''Pristiguana'' (Cretaceous Brazilian iguana) '''Family Opluridae'''<br/> '''Family Phrynosomatidae'''<br/> '''Family Polychridae'''<br/> '''Family Tropiduridae'''<br/> <!--'''Family Dinosaur-->

===Macey et al. (1997) classification of Iguanidae=== '''Family Iguanidae''' *Subfamily Corytophaninae: casquehead lizards *Subfamily Crotaphytinae: collared and leopard lizards *Subfamily Hoplocercinae: wood lizards, clubtails *Subfamily Iguaninae: marine, Fijian, Galapagos land, spinytail, rock, desert, green, and chuckwalla iguanas *Subfamily Oplurinae: Madagascan iguanids *Subfamily Phrynosomatinae: earless, spiny, tree, side-blotched and horned lizards *Subfamily Polychrotinae: anoles, leiosaurs, ''Polychrus'' *Subfamily Tropidurinae: curly-tailed lizards, neotropical ground lizards, South American swifts

===Schulte et al. (2003) classification of Iguanidae=== Here families and subfamilies are proposed as clade names, but may be recognized under the traditional Linnean nomenclature.

'''Iguanidae''' * Corytophaninae: casquehead lizards * Crotaphytinae: collared and leopard lizards * Hoplocercinae: wood lizards, clubtails * Iguaninae: marine, Fijian, Galapagos land, spinytail, rock, desert, green, and chuckwalla iguanas * Oplurinae: Madagascan iguanids * Phrynosomatinae: earless, spiny, tree, side-blotched and horned lizards * Polychrotinae: anoles, leiosaurs, ''Polychrus'' :*subclade of Polychrotinae ''Anolis'': anoles :*subclade of Polychrotinae Leiosaurini: leiosaurs ::*subclade of Leiosaurini Leiosaurae: ::*subclade of Leiosaurini Anisolepae: :*subclade of Polychrotinae ''Polychrus'' : * Tropidurinae: curly-tailed lizards, neotropical ground lizards, South American swifts :*subclade of Tropidurinae ''Leiocephalus'': curly-tailed lizards :*subclade of Tropidurinae Liolaemini: South American swifts :*subclade of Tropidurinae Tropidurini: neotropical ground lizards :

===Townsend et al. (2011), Wiens et al. (2012) and Pyron et al. (2013) classification of Iguanidae===

*Family Corytophanidae *Family Crotaphytidae *Family Dactyloidae *Family Hoplocercidae *Family '''Iguanidae''' *Family Leiocephalidae *Family Leiosauridae *Family Liolaemidae *Family Opluridae *Family Phrynosomatidae *Family Polychrotidae *Family Tropiduridae

==References== {{Reflist}}

==External links== * [http://www.jcvi.org/reptiles/families/iguanidae.php Family Iguanidae]

{{Squamata families}} {{Iguanidae}} {{Taxonbar|from=Q235589}} {{Authority control}}

Category:Iguanidae Category:Taxa named by Nicolaus Michael Oppel Category:Lizard families Category:Extant Late Cretaceous first appearances