Parastrapotherium is an extinct genus of South American land mammal that existed from the Late Oligocene (Deseadan SALMA) to the Early Miocene (Colhuehuapian SALMA). The genus includes some of the largest and smallest known astrapotherians, but has no generally recognized description.
Description
The genus was first described by Amagehino in 1895. He distinguished it from the Santacrucian (late Early Miocene) Astrapotherium based on the greater number of upper and lower molars. Although later researchers disagreed and concluded that Ameghino based his conclusion on very fragmentary materials, they mostly agreed to distinguish the genus from other groups of astrapotherians. In the mandibular canine of Parastrapotherium, the microstructure of the tooth enamel is characterised by vertical decussation with enamel prism zones bending in an undulatory pattern.
Species The following species have been recognised: Parastrapotherium cingulatum Ameghino, 1894 Parastrapotherium ephebicum Ameghino, 1894 Parastrapotherium holmbergi Ameghino, 1894 Parastrapotherium lemoinei Ameghino, 1894 Parastrapotherium trouessarti Ameghino, 1894
Distribution Fossils of Parastrapotherium have been found in:Parastrapotherium at Fossilworks.org
Oligocene Deseado Formation, Argentina Sarmiento Formation, Argentina
Miocene Cerro Bandera Formation, Argentina Sarmiento Formation, Argentina
Palaeobiology The microstructural details of its long bones indicate that Parastrapotherium was specialised for graviportal locomotion.
References
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