Chelicerata Heymons, 1901 Scorpiones Koch, 1837 - scorpions Orthosternina Pocock, 1911 see Infraorder Orthosterni Pocock, 1911 Superfamily Chactoidea Pocock, 1893 Family Chactidae Pocock, 1893 1 Genus †Araripescorpius Bouret Campos, 1986 2 Genus Chactas Gervais, 1844