Nemertina is a term that describes a type of marine worm with a long, ribbon-like body structure. There are several different synonyms for this term, including ribbon worm, proboscis worm, and bootlace worm. These organisms are known for their unique body structure, which is characterized by a muscular proboscis used for feeding and capturing prey. They are found throughout the world's oceans and play an important role in marine ecosystems. Nemertina are also sometimes referred to as ecoloies, worms of the phylum Nemertea, or Rhynchocoela. In any case, these fascinating creatures are an important part of our natural world and deserve our attention and protection.