Phylum Arthropoda Siebold, 1848 - arthropods Status: extant; Count: - 1 Subphylum Crustacea Brünnich, 1772 - crustaceans see Superclass Crustacea Pennant, 1777 Status: extant; Count: - 2 Subphylum †Trilobitomorpha Størmer, 1944 - trilobites see Superclass Trilobitomorpha Størmer, 1944 Status: fossil; Count: - 3 Subphylum Chelicerata Heymons, 1901 Status: extant; Count: - 4 Subphylum Uniramia Snodgrass, 1935 see Phylum Arthropoda Siebold, 1848 Status: extant; Count: -