''Derasmosaurus'' is an extinct

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

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 ...

rhynchocephalia Rhynchocephalia (; ) is an order of lizard-like reptiles that includes only one living species, the tuatara (''Sphenodon punctatus'') of New Zealand. Despite its current lack of diversity, during the Mesozoic rhynchocephalians were a speciose g ...

n known from the Early Cretaceous (

Albian The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...

) aged

Pietraroja Plattenkalk The Pietraroia Plattenkalk is a Cretaceous geologic Formation (geology), formation located in the Italy, Italian municipality of Pietraroja,

of Italy. The only species in the genus is ''Derasmosaurus pietrarojae''. It was originally considered to be a specimen of ''Lacerta brevicauda'' by Costa in 1866, it was later considered a specimen of the lizard '' Chometokadmon fitzingeri'' by D'Erasmo in 1915. It was described as a distinct rhynchocephalian genus in 1988. It is distinct from other indeterminate rhynchocephalians found in the Plattenkalk. It is considered to be aquatically adapted, and possibly a member of the Pleurosauridae.

References

{{Taxonbar, from2=Q3705792, from1=Q21368352 Cretaceous lepidosaurs Early Cretaceous reptiles of Europe Prehistoric reptile genera