Eutheria tana nufin wani rukunin dabbobi masu shayarwa wanda ya haɗa da dukkan dabbobi masu shayarwa, waɗanda ke haifar da ƙanana masu tasowa waɗanda aka ciyar da su a cikin mahaifa ta hanyar mahaifa. Eutherians an siffanta su da samun mafi hadaddun placenta fiye da marsupials, sauran manyan rukunin dabbobi masu shayarwa, da kuma rashin jakar da za su ɗauki 'ya'yansu. Wannan rukunin rukunin ya ƙunshi nau'ikan dabbobi masu shayarwa, tun daga kananun shre da jemagu zuwa manyan kifin kifaye da giwaye, da kuma primates, rodents, carnivores, da ungulates.