Orthocerida

Cladus: Eukaryota
Supergroup: Opisthokonta
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Spiralia
Cladus: Lophotrochozoa
Phylum: Mollusca
Classis: Cephalopoda
Subclassis: Nautiloidea
Ordo: †Orthocerida
Familiae: Brachycycloceratidae - Clinoceratidae - Dawsonoceratidae - Geisonoceratidae - Lamellorthoceratidae - Offleyoceratidae - Paraphragmitidae - Sactorthoceratidae - Sphooceratidae - Troedssonellidae