Pristiguana brasiliensis is an extinct species of an extinct monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus Pristiguana of primitive iguanid from the Upper Cretaceous.

It has been found in the Bauru Group

Bauru Group

The Bauru Group is a geological formation in Brazil whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation. The Bauru Group was divided by Fernandes and Coimbra in four formations,namely Adamantina, Uberaba Araçatuba and...

 of Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

. Its discoverers said, in 1973, that is the oldest fossil referable to the family Iguanidae

Iguanidae

Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...

. It resembles living primitive South American iguanids in "some features". It shows "similarity" to members of the related family Teiidae

Teiidae

Teiidae is a family of lizards native to the Americas, generally known as whiptails. The group includes the parthenogenic genera Cnemidophorus and Aspidoscelis, and the non-parthenogenic Tupinambis. It has over 230 member species in ten genera...

.