Chelicerata Heymons, 1901 †Eurypterida Burmeister, 1843 - eurypterids †Stylonurina Diener, 1924 1 Superfamily †Rhenopteroidea Størmer, 1951 [monotypic] 2 Superfamily †Stylonuroidea Kjellesvig-Waering, 1959 3 Superfamily †Kokomopteroidea Kjellesvig-Waering, 1966 4 Superfamily †Mycteropoidea Cope, 1886 5 Genus †Stylonuroides Kjellesvig-Waering, 1966, incertae sedis