''Proeuphractus'' 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 ...

xenarthran Xenarthra (; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos. Ex ...

, related to the modern armadillos. It lived from the Early to the Late

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

, and its fossilized remains were discovered in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

Description

This animal was quite similar to the modern

six-banded armadillo The six-banded armadillo (''Euphractus sexcinctus''), also known as the yellow armadillo, is an armadillo found in South America. The sole extant member of its genus, it was first described by Swedish zoologist Carl Linnaeus in 1758. The six-b ...

, but it was probably larger than the giant armadillo. ''Proeuphractus'' had a carapace similar to that of modern armadillos, with complete mobile bands of

osteoderm Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinc ...

s, allowing the animal to at least partially roll up. The dermal osteoderms were robust and had the same basic ornamentation, except along the carapace axis, where the osteoderms presented a torsion of the central figure towards the postero-external corner, and were devoid of central follicle. Hair dimples could however be observed along the lateral margins and the posterior border.

Classification

The genus ''Proeuphractus'' was first described in 1886 by

Florentino Ameghino Florentino Ameghino (born Giovanni Battista Fiorino Giuseppe Ameghino September 19, 1853 – August 6, 1911) was an Argentine naturalist, paleontologist, anthropologist and zoologist, whose fossil discoveries on the Argentine Pampas, especially ...

, based on fossil remains found in

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 ...

in Late Miocene terrains. The type species is ''Proeuphractus limpidus'', whose fossils have also been found in

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

. Several other species were later attributed to the genus, such as ''Proeuphractus laevis'', ''P. limus'', ''P. nanus'', ''P. recens'' and ''P. setiger'', the latter being the most ancient species, from the Early Miocene. ''Proeuphractus'' was initially considered a member of the subfamily

Euphractinae Euphractinae is an armadillo subfamily in the family Chlamyphoridae. Euphractinae are known for having a well developed osteoderm that has large cavities filled with adipose tissue, and more hair follicles with well developed sebaceous glands i ...

, close to the origin of the extant genus ''

Euphractus The six-banded armadillo (''Euphractus sexcinctus''), also known as the yellow armadillo, is an armadillo found in South America. The sole extant member of its genus, it was first described by Swedish zoologist Carl Linnaeus in 1758. The six- ...

'' (hence the genus name ''Proeuphractus''), but more recent studies tends to indicate that it was nested at the basis of the subfamily

, along with its relative ''

Macroeuphractus ''Macroeuphractus'' is a genus of extinct armadillos from the Late Miocene to Late Pliocene of South America. The genus is noted for its large size, with ''Macroeuphractus outesi'' being the largest non- pampathere or glyptodont armadillo disc ...

''.

Bibliography

*F. Ameghino. 1897. Mammiféres crétacés de l’Argentine (Deuxième contribution à la connaissance de la fauna mammalogique de couches à Pyrotherium) retaceous mammals of Argentina (second contribution to the knowledge of the mammalian fauna of the Pyrotherium Beds) Boletin Instituto Geografico Argentino 18(4–9):406-521 *F. Ameghino. 1889. Contribución al conocimiento de los mamíferos fósiles de la República Argentina ontribution to the knowledge of the fossil mammals of the Argentine Republic Actas de la Academia Nacional de Ciencias de la República Argentina en Córdoba 6:xxxii-1027 *R. Lydekker. 1894. Contributions to a knowledge of the Fossil Vertebrates of Argentina. Part II. 2. The extinct edentates of Argentina. Anales del Museo de La Plata. Paleontología Argentina 3:1-118 *G. J. Scillato-Yané, F. Góis, A. E. Zurita, A. A. Carlini, L. R. González-Ruiz, C. M. Krmpotic, C. Oliva and M. Zamorano. 2013. Los cingulata (Mammalia, Xenarthra) del "Conglomerado Osífero" (Mioceno tardío) de la Formación Ituzaingó de Entre Ríos, Argentina. In D. Brandoni, J.I. Noriega (eds.), El Neógeno de la Mesopotamia argentina 14:118-134 *^ Kieren J. Mitchell; Agustin Scanferla; Esteban Soibelzon; Ricardo Bonini; Javier Ochoa; Alan Cooper (2016). "Ancient DNA from the extinct South American giant glyptodont Doedicurus sp. (Xenarthra: Glyptodontidae) reveals that glyptodonts evolved from Eocene armadillos". Molecular Ecology. 25 (14): 3499–3508. {{Taxonbar, from=Q63522093 Prehistoric cingulates Prehistoric placental genera Miocene xenarthrans Miocene genus first appearances Miocene mammals of South America Miocene genus extinctions Neogene Argentina Fossils of Argentina Fossils of Uruguay Neogene Uruguay Fossil taxa described in 1886 Taxa named by Florentino Ameghino