Uolienas

Uolienas is a genus of extinct marsupials that lived during the Miocene epoch, approximately 20-15 million years ago. They were discovered in Argentina and Uruguay, and their fossils are found mainly in sedimentary rocks from the Pictogramma formation.

Uolienas fossils are characterized by their distinctive dental features, which include a sloping dental arcade and a lack of accessory shearing crests on the molars. They were small to medium-sized marsupials, likely weighing between 1-5 kilograms. Their body shape and physical characteristics are not well-documented due to the limited availability of fossils.

The classification of Uolienas has been the subject of debate among paleontologists. Some researchers believe that it belongs to the family Paurodontidae, which includes other early marsupials, while others propose that it is more closely related to the family Macropodidae, which includes modern kangaroos and wallabies.

The diet and behavior of Uolienas are not well-understood, but it is believed that they were herbivores or omnivores. Their limbs were likely adapted for jumping or hopping, which would have been an effective means of locomotion in their loose, sandy habitat.

Uolienas provides valuable insights into the evolution of marsupials in South America during the Miocene epoch. Further study of its fossils is necessary to determine the exact relationships between Uolienas and other extinct or extant marsupials.