Chelicerata Heymons, 1901 †Phalangiotarbida Haase, 1890 1 Family †Devonotarbidae Poschmann & Dunlop, 2012 [monotypic] 2 Family †Anthracotarbidae Kjellesvig-Waering, 1969 [monotypic] 3 Family †Architarbidae Karsch, 1882 4 Family †Heterotarbidae Petrunkevitch, 1913 [monotypic] 5 Family †Opiliotarbidae Petrunkevitch, 1945 [monotypic]