“…Litopterna is a diverse clade of SANUs recorded in South America from at least the late Paleocene (Peligran SALMA [Gelfo et al, 2009], although possibly they were present since the Tiupampan SALMA [Muizon and Cifelli, 2000]), to the late Pleistocene (Bond et al, 2001). Several clades are recognized within Litopterna: Protolipternidae, Notonychopidae, Adianthidae, Macraucheniidae, and Proterotheriidae (Cifelli, 1983(Cifelli, , 1993Schmidt, 2015;Forasiepi et al, 2016). The Sparnotheriodontidae has been variably treated as "Condylarthra" (Cifelli, 1983(Cifelli, , 1993 or as a member of Litopterna (Soria, 2001).…”