Chelicerata Heymons, 1901 Ricinulei Thorell, 1876 [monotypic] - ricinuleids 1 Suborder †Primoricinulei Wunderlich, 2015 2 Suborder †Palaeoricinulei Selden, 1992 3 Suborder Neoricinulei Selden, 1992 [monotypic]