Arthropoda is the largest of all the phylums and includes all arachnids, insects, myraipods, and crustaceans. An Arthropoda has a jointed appendages, a segmented body, and an exoskeleton. So Arthropoda include all species of lobsters, crabs, ants, butterflies, spiders, and much more. There are around a total of thirty-million species of Arthropoda.