Ko te whakarōpūtanga o te archaea, me te o prokaryotes i roto i te whānui, ko te tere te neke me te āpure tautohetohe. Kua whakaaro ngā pūnaha whakarōpūtanga o nāianei ki te whakarite archaea ki ngā rōpū o ngā rauropi e faaite āhuatanga hanganga me ngā tupuna noa. whakawhirinaki enei whakarōpūtanga tino i runga i te whakamahi o te raupapa o te ira ribosomal RNA ki te whakaatu hononga i waenganui i ngā rauropi (phylogenetics rāpoi). Ko te nuinga o te culturable me pai-tirohia momo o archaea he mau melo o rua phyla matua, te Euryarchaeota me Crenarchaeota. Kua hanga āta ētahi atu rōpū. Hei tauira, kua hoatu te momo motuhake Nanoarchaeum equitans, i kitea i roto i 2003, kua tona ake phylum, te Nanoarchaeota. Kua whakaarohia hoki te pūnaha whakarōpūtanga o Korarchaeota. Kei roto i enei whakarōpūtanga te nuinga o ngā momo e rua e pā ana ki te eukarchaeota, engari i kitea tata nei i roto i
Euryarchaeota me te Crenarchaeota