''Anchaurosaurus'' (meaning "morning lizard" in

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

) is an extinct

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 ...

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 ...

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 ...

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an Autonomous regions of China, autonomous region of China. Its border includes two-thirds of the length of China's China–Mongolia border, border with the country of Mongolia. ...

, China. It belongs to an extinct clade of iguanians called

Gobiguania Gobiguania is an extinct clade of iguanian lizards from the Late Cretaceous. All known gobiguanians are endemic to the Gobi Desert of Mongolia. Gobiguania was given a phylogenetic definition by Jack Conrad and Mark Norell in 2007 as all taxa more ...

that was endemic to the

Gobi Desert The Gobi Desert (, , ; ) is a large, cold desert and grassland region in North China and southern Mongolia. It is the sixth-largest desert in the world. The name of the desert comes from the Mongolian word ''gobi'', used to refer to all of th ...

during the Late Cretaceous. The

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

, ''Anchaurosaurus gilmorei'', was named in 1995 on the basis of a well-preserved skull and incomplete skeleton from the

Djadochta Formation The Djadochta formation (sometimes transcribed and also known as Djadokhta, Djadokata, or Dzhadokhtskaya) is a highly fossiliferous geological formation in Central Asia, Gobi Desert, dating from the Late Cretaceous period, about 75 million ...

. Compared to other iguanians, ''Anchaurosaurus'' has a relatively elongated skull, large eye sockets, and higher

tooth crown In dentistry, the crown is the visible part of the tooth above the gingival margin and is an essential component of dental anatomy. Covered by Tooth enamel, enamel, the crown plays a crucial role in cutting, tearing, and grinding food. Its shap ...

Phylogenetic analysis In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data ...

indicates that among gobiguanians, ''Anchaurosaurus'' is most closely related to '' Zapsosaurus'' from Mongolia. Below is a

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

from Daza ''et al.'' (2012) showing the phylogenetic relationships of ''Anchaurosaurus'':

References

Cretaceous lizards Late Cretaceous lepidosaurs of Asia Fossil taxa described in 1995 Prehistoric lizard genera {{paleo-lizard-stub