“…The pre-late Oligocene record of Sparassodonta is remarkably poor, with most occur¬ rences representing basal sparassodonts (e.g., Patene) or proborhyaenids, a grouping of exclusively Paleogene sparassodonts only distantly related to most Miocene forms (except possibly thylacosmilids; see Babot, 2005;Forasiepi et al, 2015;Engelman et al, 2017). If proborhyaenids are deeply nested within Borhyaenoidea, as is consistently recovered by many studies (Muizon, 1999;Babot et al, 2002;Forasiepi, 2009;Engelman and Croft, 2014;Forasiepi et al, 2015;Suarez et al, 2016;Muizon et al, 2018), then the major lineages of late Cenozoic sparassodonts (e.g., hathliacynids, borhyaenids) must have originated by the mid¬ dle Eocene (Vacan subage of the Casamayoran SALMA), based on the earliest widely accepted occurrence of a proborhyaenid (Babot et al, 2002;Powell et al, 2011), or potentially even the early Eocene, based on possible proborhyaenid remains from the Las Violetas Fauna (Gelfo et al, 2010;Krause et al, 2017). An early or middle Eocene divergence of major sparassodont clades is supported by a recent report of a possible borhyaenid from the middle Eocene locality of La Barda, Argentina (Lorente et al, 2016).…”