''Datheosaurus'' ("Dathe's lizard") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

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 ...

caseasaur Caseasauria is one of the two main clades of early synapsids, the other being the Eupelycosauria. Caseasaurs are currently known only from the Late Carboniferous and the Permian, and include two superficially different families, the small insect ...

. It was at least in length. It lived during the Latest

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

to Early

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

. It was named for Ernst Dathe (1845–1917), the German geologist who first announced the fossil find.

Discovery and history

It was originally described in 1905 on a basis of a specimen from late Carboniferous deposits in Poland. It was later considered a synonym of ''

Haptodus ''Haptodus'' is an extinct genus of basal sphenacodonts, a member of the clade that includes therapsids and hence, mammals. It was at least in length. It lived in present-day France during the Early Permian. It was a medium-sized predator, fe ...

'' by several authors, but subsequent examination has found it be a caseid rather a sphenacodont. This was confirmed by cladistic analysis, which recovered ''Datheosaurus'' as a basal

caseid Caseidae are an extinct family of basal synapsids that lived from the Late Carboniferous to Middle Permian between about 300 and 265 million years ago. Fossils of these animals come from the south-central part of the United States (Texas, Oklaho ...

References

Caseidae Prehistoric synapsid genera Carboniferous synapsids Cisuralian synapsids of Europe Fossil taxa described in 1905 Fossils of Poland {{Paleo-synapsid-stub