Chordata Bateson, 1885 - chordates Class †Ostracophori Order †Cycliae [monotypic] Family †Palaeospondylidae Stürtz, 1899 [monotypic] see Family Dipteridae Owen, 1846 1 Genus †Palaeospondylus Traquair, 1890 [monotypic] see Genus Dipterus Sedgwick & Murchison, 1829