Phylum Chordata Bateson, 1885 - chordates Class †Conodonta Eichenberg, 1930 Subclass †Conodonti Branson see Subclass Conodonta Eichenberg, 1930 Order †Prioniodontida Dzik Family †Icriodontidae Müller & Müller Genus †Icriodus Branson & Mehl, 1933 †Icriodus iowaensis Youngquist & Peterson