†subfamily Mesembriornithinae (terror bird)
Reptilia - Gruiformes - Phorusrhacidae
Synonyms: Hermosiornidae Rovereto 1914, Hermosiorninae Rovereto 1914, Prophororhacidae, Prophororhacinae
Parent taxon: Phorusrhacidae according to H. M. F. Alvarenga and E. Holfing 2003
Sister taxa: Ameghinornis, Kelenken, Patagornithinae, Phorusrhacinae
Subtaxa: Mesembriornis
Ecology: ground dwelling carnivore