Chamaeleontiformes is a hypothesized

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

(evolutionary grouping) of

iguania Iguania is an infraorder of squamate reptiles that includes iguanas, chameleons, agamids, and New World lizards like anoles and phrynosomatids. Using morphological features as a guide to evolutionary relationships, the Iguania are believed t ...

n lizards defined as all taxa sharing a more recent common ancestor with ''

Chamaeleo chamaeleon ''Chamaeleo'' is a genus of chameleons in the family Chamaeleonidae. Most species of the genus ''Chamaeleo'' are found in sub-Saharan Africa, but a few species are also present in northern Africa, southern Europe, and southern Asia east to Indi ...

'' (the common chamaeleon) than with '' Hoplocercus spinosus'' (the Brazilian spiny-tailed lizard), ''

Polychrus marmoratus ''Polychrus marmoratus'' or many-colored bush anole is a species of bush anole. It is also commonly referred to as the monkey lizard due to its slow movement. The lizard has many predators, including spiders and primates. Description ''Polyc ...

'' (bush lizard), or '' Iguana iguana'' (green iguana). It was named by paleontologist Jack Conrad in 2008 to describe a clade recovered in his

phylogenetic analysis In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

that included the extinct genus ''

Isodontosaurus ''Isodontosaurus'' is an extinct genus of iguanian lizard from the Late Cretaceous of Mongolia and China. The type species is ''Isodontosaurus gracilis''. ''Isodontosaurus'' is part of an extinct group of Late Cretaceous iguanians called Gobiguan ...

'', the extinct family

Priscagamidae Priscagamidae is an extinct family of iguanian lizards known from the Late Cretaceous of Mongolia and China and the Eocene of India, spanning a range from 75 to 54 million years ago. It includes the genera ''Heterodontagama'', ''Mimeosaurus'', '' ...

, and the living clade Acrodonta, which includes

agamid Agamidae is a family of over 300 species of iguanian lizards indigenous to Africa, Asia, Australia, and a few in Southern Europe. Many species are commonly called dragons or dragon lizards. Overview Phylogenetically, they may be sister to the I ...

s and

chameleon Chameleons or chamaeleons (family Chamaeleonidae) are a distinctive and highly specialized clade of Old World lizards with 202 species described as of June 2015. The members of this family are best known for their distinct range of colors, bein ...

s. It is a

stem-based taxon Phylogenetic nomenclature is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional approach, in which taxon names are defined by a '' type'', which ...

and one of two major clades within Iguania, the other being

Pleurodonta Pleurodonta (from Greek '' lateral teeth'', in reference to the position of the teeth on the jaw) is one of the two subdivisions of Iguania, the other being Acrodonta ('' teeth on the top f the jaw'). Pleurodonta includes all families previously ...

. Below is a

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

from Daza ''et al.'' (2012) showing this phylogeny: Other analyses place Priscagamidae outside Iguania altogether, resulting in a Chamaeleontiformes that only includes ''Isodontosaurus'' and Acrodonta. Below is a cladogram from Conrad (2015) with this phylogeny:

References

Iguanomorpha {{lizard-stub