His studies on bees, myriapods and termites were monumental. They form a phylum which includes insects, arachnids, myriapods, and crustaceans. Pauropoda is another small group of small myriapods. The legs of insects and myriapods are uniramous. Troglofaunal species include spiders, insects, myriapods and others. Arthropods form the phylum Euarthropoda, which includes insects, arachnids, myriapods, and crustaceans. Symphyla are small, cryptic myriapods without eyes and without pigment. Insects form a single clade, closely related to crustaceans and myriapods. Adults feed on slugs, myriapods, spiders, beetles and grasshoppers. Millipede sperm lack flagella, a unique trait among myriapods. The term is also used in other arthropod groups such as crustaceans, arachnids and myriapods. The phylogenetic classification of myriapods is still debated. Banded mongoose feed primarily on insects, myriapods, small reptiles, and birds. Cave spiders feed on smaller invertebrates, most frequently myriapods and slugs. This article outlines the basic elements of four arthropod groups&colon; insects, myriapods, crustaceans and chelicerates.