Chelicerata Heymons, 1901 †Eurypterida Burmeister, 1843 - eurypterids †Eurypterina Burmeister, 1843 †Diploperculata Lamsdell, Hoşgör & Selden, 2013 Superfamily †Carcinosomatoidea Størmer, 1934 Family †Mixopteridae Caster & Kjellesvig-Waering, 1955 Genus †Mixopterus Ruedemann, 1920