Chelicerata Heymons, 1901
   Opiliones Sundevall, 1833 - harvestmen
     Phalangida Bristowe, 1949
       Suborder Laniatores Thorell, 1876 - armored harvestmen
         Infraorder Grassatores Kury, 2002
           Superfamily Zalmoxoidea Sørensen, 1886
             Family Icaleptidae Kury & Pérez-González, 2002