Kinorhyncha is a group of marine invertebrates characterized by their segmented bodies and spiny heads. This phylum is also known as Echinoderes, Homalorhagida, or Cyclorhagida. Other common names for this group of animals are mud dragons, spoon worms, or arrow worms. The name 'mud dragon' hints at the elusive nature of these tiny creatures, which burrow in the sand and are rarely seen. 'Spoon worms' refers to the scooping motion they use to feed on organic matter in the sediment, while 'arrow worms' refers to their torpedo-like shape and predatory behavior. Regardless of the synonym used, Kinorhyncha is a fascinating and diverse group of animals that continue to intrigue scientists and curious observers alike.