Complex sentence: They existed from the Miocene to early Pleistocene, and most of species were found in Eurasia and all were scimitar-toothed (having broad and mildy elongated upper canines).
Split into simpler sentences: They existed from the Miocene to early Pleistocene, with most species being found in Eurasia. Members of this tribe were all scimitar-toothed (having broad and mildy elongated upper canines).