Full reference: J. -B. Lamarck. 1801. Système des Animaux sans Vertèbres, ou Tableau général des classes, des ordres et des genres de ces animaux. 8:1-432
Parent taxon: Chordata according to M. Richter et al. 2017
See also Brusca et al. 2016, Dineley and Metcalf 1999, Donoghue and Smith 2001, Haeckel 1866, Nelson et al. 2016, Nielsen 2012, Nielsen 2012, Shoshani et al. 1989, Shu et al. 1999, Van Der Laan 2019 and Zrzavy et al. 1998
Sister taxa: Cephalochordata, Conodontophorida, Craniata, Metaspriggina, Olfactores, Pikaidae, Tunicata, Undichna
Subtaxa: Acrania Agnatha Ammopus Anaspidomorphi Apedolepis Artenolepis Cephalaspidomorpha Craniota Cyclostomi Eosaurus Eotetrapoda Galeaspida Gnathostomata Herpetichthyes Hoplichnus Hypichthyes Lepidotosaurus Mannodon Myzichthyes Ophis Osteostracomorphii Ostracophori Pachycardia Palaeoxyris Petromyzontida Petromyzontomorphi Pituriaspida Protetrapoda Saurornia Thelodontomorphi Thoracophis Tidaeus Toxichnus Zamponiopteron