WAnachlysictis gracilis is an extinct carnivorous mammal belonging to the group Sparassodonta, which were metatherians that inhabited South America during the Cenozoic. Unlike other remains assigned to the family Thylacosmilidae that had been found previously, Anachlysictis is the first record of such borhyaenoids in northern South America, and also most primitive and ancient in the family. This species was found in the Villavieja Formation in the area of La Venta in Colombia, a famous fossil deposit in the Middle Miocene, based on fragments that include a front portion of the lower jaw, with an incipient molar tooth and a piece of carnassial from the front of the maxilla.
WBorhyaena is an extinct genus of South American metatherian, living between 17.5 and 15.5 million years ago in Patagonia, Argentina and Chile.
WBorhyaenidae is an extinct metatherian family of low-slung, heavily built predatory mammals in the order Sparassodonta. Borhaenids are not true marsupials, but members of a sister taxon, Sparassodonta. Like most metatherians, borhyaenids and other sparassodonts are thought to have had a pouch to carry their offspring around. Borhyaenids had strong and powerful jaws, like those of the unrelated placentalians Hyaenodon and Andrewsarchus, for crushing bones. Borhyaenids grew up to an average of 5 to 6 feet long. Borhyaena is the type genus of this group.
WCladosictis is an extinct genus of South American metatherian from Patagonia, Argentina and Chile.
WDukecynus is an extinct genus of meat-eating metatherian belonging to the order Sparassodonta, which lived in South America during the Middle Miocene (Laventan), between about 13.8 and 11.8 million years ago. The name of the genus meaning "Duke dog", for Duke University and the Greek word cynos, dog, for the pretended similarity of this animal with dogs. A single species known so far, Dukecynus magnus. The species name "magnus" derives from Latin for big, to reflect their great size.
WHondadelphys is an extinct genus of carnivorous sparassodonts, known from the Middle Miocene of Colombia. The type species, H. fieldsi, was described in 1976 from the fossil locality of La Venta, which hosts fossils from the Villavieja Formation. Hondadelphys was originally interpreted as belonging to the opossum family Didelphidae, but subsequently assigned to its own family, Hondadelphidae and interpreted as a basal sparassodont. The genus name refers to the Honda Group, the stratigraphic group in which the fossils of this animal were first found, combined with delphys (Greek for "womb", a common suffix used for opossum-like metatherians).
WLycopsis is an extinct genus of South American metatherian, that lived during the Miocene in Argentina and Colombia.
WProborhyaenidae is an extinct family of metatherian mammals of the order Sparassodonta, which lived in South America from the Eocene (Mustersan) until the Oligocene (Deseadan). Sometimes it has been included as a subfamily of their relatives, the borhyaenids. Body mass estimates suggest that proborhyaenids could weigh up to 150 kilograms (330 lb), making them some of the largest known metatherians. Proborhyaenid remains have been found in western Bolivia, Uruguay, southern Brazil, and the provinces of Mendoza, Salta, and Chubut, in Argentina.
WSparassodonta is an extinct order of carnivorous metatherian mammals native to South America. They were once considered to be true marsupials, but are now thought to be either a sister taxon to them, or considerably distantly related, part of a separate clade of Gondwanan metatherians. A number of these mammalian predators closely resemble placental predators that evolved separately on other continents, and are cited frequently as examples of convergent evolution. They were first described by Florentino Ameghino, from fossils found in the Santa Cruz beds of Patagonia. Sparassodonts were present throughout South America's long period of "splendid isolation" during the Cenozoic; during this time, they shared the niches for large warm-blooded predators with the flightless terror birds. Previously, it was thought that these mammals died out in the face of competition from "more competitive" placental carnivorans during the Pliocene Great American Interchange, but more recent research has showed that sparassodonts died out long before eutherian carnivores arrived in South America. Sparassodonts have been referred to as borhyaenoids by some authors, but currently the term Borhyaenoidea refers to a restricted subgroup of sparassodonts comprising borhyaenids and their close relatives.
WProthylacinus is an extinct genus of South American metatherian, that lived during the Early Miocene.
WSparassodonta is an extinct order of carnivorous metatherian mammals native to South America. They were once considered to be true marsupials, but are now thought to be either a sister taxon to them, or considerably distantly related, part of a separate clade of Gondwanan metatherians. A number of these mammalian predators closely resemble placental predators that evolved separately on other continents, and are cited frequently as examples of convergent evolution. They were first described by Florentino Ameghino, from fossils found in the Santa Cruz beds of Patagonia. Sparassodonts were present throughout South America's long period of "splendid isolation" during the Cenozoic; during this time, they shared the niches for large warm-blooded predators with the flightless terror birds. Previously, it was thought that these mammals died out in the face of competition from "more competitive" placental carnivorans during the Pliocene Great American Interchange, but more recent research has showed that sparassodonts died out long before eutherian carnivores arrived in South America. Sparassodonts have been referred to as borhyaenoids by some authors, but currently the term Borhyaenoidea refers to a restricted subgroup of sparassodonts comprising borhyaenids and their close relatives.
WThylacosmilidae is an extinct family of metatherian predators, related to the modern marsupials, which lived in South America between the Miocene and Pliocene epochs. Like other South American mammalian predators that lived prior to the Great American Biotic Interchange, these animals belonged to the order Sparassodonta, which occupied the ecological niche of many eutherian mammals of the order Carnivora from other continents. The family's most notable feature are the elongated, laterally flattened fangs, which is a remarkable evolutionary convergence with other saber-toothed mammals like Barbourofelis and Smilodon.
WThylacosmilus is an extinct genus of saber-toothed metatherian mammals that inhabited South America from the Late Miocene to Pliocene epochs. Though Thylacosmilus looks similar to the "saber-toothed cats", it was not a felid, like the well-known North American Smilodon, but a sparassodont, a group closely related to marsupials, and only superficially resembled other saber-toothed mammals due to convergent evolution. A 2005 study found that the bite forces of Thylacosmilus and Smilodon were low, which indicates the killing-techniques of saber-toothed animals differed from those of extant species. Remains of Thylacosmilus have been found primarily in Catamarca, Entre Ríos, and La Pampa Provinces in northern Argentina.