Paleoecology of the mammalian carnivores (Metatheria, Sparassodonta) of the Santa Cruz Formation

PREVOSTI, F.J.; FORASIEPI, A.M.; ERCOLI, M.; TURAZZINI, G.

Early Miocene Paleobiology in Patagonia: high-latitude paleocommunities of the Santa Cruz Formation

Cambridge University Press

Lugar: Cambridge; Año: 2012; p. 173 - 193

South America had an endemic mammalian fauna for muchof the Cenozoic, largely evolved during its long isolation.The predator guild was mainly occupied by metatherians(Sparassodonta), as well as large terrestrial birds (Phorusrhacidae),agile terrestrial crocodiles (Sebecidae), and giantsnakes (Madtsoiidae). Sparassodonta was a diverse clade,recorded from the Paleocene to the Middle Pliocene, withits acme in the late Early Miocene (Santacrucian Age).In this chapter, we review the paleoecology of thesparassodonts known from the Santa Cruz Formation andinclude new results obtained by geometric morphometricanalyses. The Santa Cruz Formation contains 11 sparassodontspecies: six Hathliacynidae (Acyon tricuspidatus,Cladosictis patagonica, Sipalocyon gracilis, Sipalocyonobusta, Pseudonotictis pusillus, Perathereutes pungens)and five Borhyaenoidea (Prothylacynus patagonicus,Lycopsis torresi, and three Borhyaenidae, Borhyaenatuberata, Acrocyon sectorius, and Arctodictis munizi).These sparassodonts were mainly hypercarnivores exhibitingdifferent locomotor abilities (from scansorial to terrestrial),and a wide range of body masses (from 1 kg to morethan 50 kg). The reconstruction of the Santacrucian predatorguild suggests that there was good ecological separationwithin the sparassodonts, determined by particular combinationsof body size, locomotion, and diet. The diversityof sparassodonts recorded in the Santa Cruz Formation (11species) and in the Estancia La Costa Member (sevenspecies), is similar to that observed in present and pastplacental hypercarnivore communities.