''Retinosaurus'' (meaning "amber lizard") is an extinct genus of scincomorph lizard from the

Early Cretaceous The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Pro ...

Myanmar Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John C. Wells, Joh ...

. The genus contains a single species, ''Retinosaurus hkamtiensis'', known from a specimen preserved in amber.

Discovery and naming

The holotype specimen, GRS 29689, was legally obtained from a Myanmar gem dealer in 2019. It was subsequently announced in a preprint in October 2021, and validly described as a new genus and species of lizard by Čerňanský ''et al.'' in January 2022. The fossil was discovered in the Hkamti amber site of Myanmar, which dates to the early Albian, approximately 110 million years ago. The holotype, which represents a juvenile individual, includes a well-preserved articulated skull, partial postcrania, and skin impressions. In addition to the lizard fossil material, the amber also contains several coleopterans. The generic name, "''Retinosaurus''", is derived from the Greek words "retine", referring to liquid resins created by trees, and "saurus", meaning "lizard". The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

, "''hkamtiensis''", references Hkamti, the type locality.

Classification

In all but one of the phylogenetic analyses performed by the describing authors, ''Retinosaurus'' was recovered as a Pan-

xantusiid Night lizards (family Xantusiidae) are a group of small scincomorph lizards, averaging from less than to over snout–vent length. Most species are viviparous (live-bearing), with the exception of those in the genus '' Cricosaura''. The family ...

. Most phylogenies resulted with ''Retinosaurus'' as a sister taxon to a clade formed by '' Tepexisaurus'' + Xantusiidae. Because the holotype represents an immature individual, the authors explain that any phylogenetic results should be treated with caution.

References

{{taxonbar, from = Q110921227 Scincomorpha Fossil taxa described in 2022 Cretaceous lizards Early Cretaceous reptiles of Asia Fossils of Myanmar