Chelicerata Heymons, 1901 †Eurypterida Burmeister, 1843 - eurypterids †Eurypterina Burmeister, 1843 Superfamily †Onychopterelloidea Lamsdell, 2011 [monotypic] Family †Onychopterellidae Lamsdell, 2011 Genus †Tylopterella Størmer, 1951