Reptilia - Sphenisciformes - Spheniscidae
Synonyms: Isotremornis Ameghino 1905, Metancylornis Ameghino 1905
Full reference: F. Ameghino. 1891. Enumeracion de las aves fosiles de la Republica Argentina. Revista Argentina de Historia Naturales 1:441-453
Parent taxon: Spheniscidae according to G. G. Simpson 1972
Sister taxa: Anthropodyptes, Anthropornis, Archaeospheniscus, Arthrodytes, Dege, Delphinornis, Duntroonornis, Eretiscus, Eudyptes, Eudyptula, Inguza, Korora, Madrynornis, Marambiornis, Marplesornis, Megadyptes, Mesetaornis, Nucleornis, Pachydyptes, Palaeeudyptes, Palaeeudyptinae, Palaeospheniscinae, Palaeospheniscus, Paraptenodytinae, Platydyptes, Pseudaptenodytes, Pygoscelis, Spheniscinae, Spheniscus, Tereingaornis, Tonniornis, Wimanornis
Subtaxa: Isotremornis nordenskjoldi, Paraptenodytes antarcticus, Paraptenodytes brodkorbi, Paraptenodytes robustus
Type: Palaeospheniscus antarcticus
Ecology: ground dwelling carnivore