''Chometokadmon'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

anguimorph The Anguimorpha is a suborder of squamates. The group was named by Fürbringer in 1900 to include all autarchoglossans closer to '' Varanus'' and ''Anguis'' than ''Scincus''. These lizards, along with iguanians and snakes, constitute the propo ...

lizard from the Early Cretaceous of Italy. The type and only species is ''Chometokadmon fitzingeri'', named by Italian zoologist

Oronzio Gabriele Costa Oronzo Gabriele Costa (26 August 1787, Alessano – 7 November 1867 Naples) was an Italian zoologist. At first a physician, he taught zoology at the University of Naples. He wrote 126 papers on various subjects, principally entomology, and in 184 ...

in 1864. It is known from only one specimen, a nearly complete skeleton from the comune of

Pietraroja Pietraroja is a mountain ''comune'' (municipality) in the province of Benevento in Campania, southern Italy. It is approximately 50 km by car from Benevento, in direction north-west, 83 km from Naples in direction north-east and appr ...

in the Apennine Mountains from the sediments of the Pietraroia Plattenkalk. Costa identified the specimen as a lizard, but in 1915 paleontologist Geremia d'Erasmo reclassified the skeleton as that of a rhynchocephalian on the basis of another rhynchocephalian specimen Costa had described, which d'Erasmo thought belonged to the same species. Later studies of the anatomy of these two specimens revealed that they belonged to two different species; Costa's ''Chometokadmon'' was a lizard whereas the other specimen, renamed ''

Derasmosaurus ''Derasmosaurus'' is an extinct species of rhynchocephalian known from the Pietraroja Plattenkalk of Italy. It was originally considered to be a specimen of ''Lacerta brevicauda'' by Costa in 1866, it was later considered a specimen of the l ...

'' in honor of d'Erasmo, was a rhynchocephalian. The first detailed description of ''Chometokadmon'' came in 2006, allowing it to be incorporated into a

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 ...

of lizards. The analysis placed ''Chometokadmon'' as a member of the clade (evolutionary grouping) Anguimorpha, which includes

Anguidae Anguidae refers to a large and diverse family of lizards native to the Northern Hemisphere. Common characteristics of this group include a reduced supratemporal arch, striations on the medial faces of tooth crowns, osteoderms, and a lateral fold ...

Xenosauridae Xenosauridae is a family of anguimorph lizards whose only living representative is the genus ''Xenosaurus'', which is native to Central America. Xenosauridae also includes the extinct genera '' Exostinus'' and '' Restes''. Also known as knob-scal ...

, and

Varanoidea Varanoidea is a superfamily of lizards, including the well-known family Varanidae (the monitors and goannas). Also included in the Varanoidea are the Lanthanotidae (earless monitor lizards), and the extinct Palaeovaranidae. Throughout their lon ...

References

Cretaceous lizards Early Cretaceous reptiles of Europe Fossil taxa described in 1864 Taxa named by Oronzio Gabriele Costa {{paleo-lizard-stub