Ochrophyta | see Heterokontae |
Onychophora | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>BILATERIA>PROTOSTOMATA>ECDYSOZOA>PANARTHROPODA>ONYCHOPHORA |
Oomycota | EUKARYA>CHROMALVEOLATA>HETEROKONTAE>OOMYCOTA |
Opalinata | EUKARYA>CHROMALVEOLATA>HETEROKONTAE>OPALINIDA |
Opisthokonta | see Unikonta |
Orthonectida | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>METAZOA>BILATERIA>PROTOSTOMATA>LOPHOTROCHOZOA>EUTROCHOZOA>ORTHONECTOZOA |
Osteichthyes | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>BILATERIA>DEUTEROSTOMATA>VERTEBRATA>GNATHOSTOMATA>OSTEICHTHYES |
Osteostracomorphi | EUKARYA>UNIKONTA>OPISTHOKONTA>ANIMALIA>BILATERIA>DEUTEROSTOMATA>VERTEBRATA>OSTEOSTRACOMORPHI |
Oxyphotobacteria | EUBACTERIA>OXYPHOTOBACTERIA |