''Anayatherium'' 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 n ...

of notoungulate belonging to the family

Leontiniidae Leontiniidae is an extinct family comprising eighteen genera of notoungulate mammals known from the Middle Eocene (Mustersan) to Late Miocene (Huayquerian) of South America South America is a continent entirely in the Western Hemisph ...

. It lived during the Late

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

, 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 souther ...

Description

It was a large-sized and heavy-shaped animal, that could reach the size of a cow. It may have reached a length of 2.5 meters ; its skull was 45 centimeters long, and its weight may have exceeded 350 kilograms. ''Anayatherium'' was characterized by a very short muzzle, compared to other leontiniids. The shortening of the muzzle was reflected in the dentition by the loss of one of the upper teeth, probably a canine. The first upper incisor was larger than the second, as in '' Scarrittia'', while the third and fourth premolars had vertical lingual grooves, as in '' Leontinia''. The second upper incisor was of a typical shape, unlike ''Leontinia'' in which it had instead the shape of a canine ; in ''Anayatherium'', the first incisor took the place of the canine. Unlike ''Scarrittia'', the premolars had grooved protocones. The molars were low-crowned (brachydont), and only slightly high-crowned (hypsodont) on the lingual side.

Classification

The genus ''Anayatherium'' was first described in 2015 by Shockey, based on fossils found in the Salla Formation of

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

, in terrains dated from the Late

. Two species were attributed to the genus, ''A. ekecoa'', the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

, and ''A. fortis'', mainly distinguished by their respective sizes. ''Anayatherium'' was a Leontiniid, a family of Notoungulates typical of the Oligocene and

Miocene The Miocene ( ) is the first 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 means "less recent" ...

, with heavy and large bodies. ''Anayatherium'' seems to have belonged to a clade including ''

Colpodon ''Colpodon'' is an extinct genus of herbivorous mammal, belonging to the order Notoungulata. It lived during the Early Miocene, in what is today Argentina and Chile, in South America. Description This animal is almost exclusively known from c ...

'', ''

Ancylocoelus ''Ancylocoelus'' is an extinct genus of mammal, belonging to the order Notoungulata. It lived during the Late Oligocene, in what is today Argentina, in South America. Description This genus is only known from cranial remains, but comparison w ...

'', and the two derived genera ''Leontinia'' and ''Scarrittia''.

Paleoecology

Like all leontiniids, ''Anayatherium'' was a heavy quadrupedal

folivore In zoology, a folivore is a herbivore that specializes in eating leaves. Mature leaves contain a high proportion of hard-to-digest cellulose, less energy than other types of foods, and often toxic compounds.Jones, S., Martin, R., & Pilbeam, D. ( ...

. Fossils of ''Anayatherium'' are unusually rare for a leontiniid ; leontiniids were usually common animals in their habitats. It is possible that the Salla Formation may not have been particularly suited environment for leontiniids during the Late Oligocene.

Bibliography

*B. J. Shockey. 2005. New leontinidids (Class Mammalia, Order Notoungulata, Family Leontiniidae) from the Salla beds of Bolivia (Deseadan, Late Oligocene). Bulletin of the Florida Museum of Natural History 45(4):249-260 *B. J. Shockey, J. J. Flynn, D. A. Croft, P. Gans, and A. R. Wyss. 2012. New leontiniid Notoungulata (Mammalia) from Chile and Argentina: comparative anatomy, character analysis, and phylogenetic hypotheses. American Museum Novitates 3737:1-64 Toxodonts Oligocene mammals of South America Paleogene Bolivia Fossils of Bolivia Fossil taxa described in 2005 Prehistoric placental genera {{paleo-mammal-stub