The phylum Onychophora comprises about 80 species in two families, one living in the tropics and one in the Southern Hemisphere. They are commonly known as Velvet Worms and look rather like slugs with 14 to 43 pairs of legs, or long caterpillars. They live in damp places and are often brightly colored with an iridescent surface and can be up to 15 centimetres long.