''Guilielmofloweria'' is an extinct genus of proterotheriid

litoptern Litopterna (from grc, λῑτή πτέρνα "smooth heel") is an extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of South American ungulates that were endemic to the continent, until th ...

that lived from the Middle to Late Eocene of what is now

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

. Fossils have been found in the

Sarmiento Formation The Sarmiento Formation (Spanish: ''Formación Sarmiento''), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid- ...

of Argentina.

Taxonomy

''Guilielmofloweria'' was first named in 1901 by Florentino Ameghino based on fragmentary remains found in the Sarmiento Formation of Argentina, in rocks dating back to the Middle Eocene. He originally considered it a member of the

pantodont Pantodonta is an extinct suborder (or, according to some, an order) of eutherian mammals. These herbivorous mammals were one of the first groups of large mammals to evolve (around 66 million years ago) after the end of the Cretaceous. The la ...

family Pantolambdidae, but recent studies have shown this to be incorrect, as Richard Cifelli considered it as a member of the litoptern family Proterotheriidae, more specifically within the subfamily Anisolambdinae. Anisolambdinae (also called Anisolambdidae in some studies) was proposed to unite the primitive and earlier forms '' Anisolambda'', '' Eolicaphrium'', '' Heteroglyphis'', '' Lambdaconops'', '' Paranisolambda'', '' Protheosodon'', '' Wainka'' and '' Xesmodon''. However, the phylogenetic analysis of McGrath and colleagues recovered the included genera to neither form their own clade, or to universally represent basal taxa outside the genera of Proterotheriinae per Soria, making Anisolambdinae a

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of converg ...

group of unrelated organisms.

References

{{Taxonbar, from=Q113961687 Proterotheriids Prehistoric placental genera Eocene mammals of South America Divisaderan Mustersan Paleogene Argentina Fossils of Argentina Fossil taxa described in 1901 Taxa named by Florentino Ameghino Golfo San Jorge Basin Sarmiento Formation