Lancelets are small, fish-like creatures that belong to the phylum Cephalochordata. They are marine animals and are found in shallow waters around the world. Lancelets have a simple body plan and lack a backbone, making them invertebrates. They are filter feeders and use their mucus to trap food particles. Lancelets are an important part of the marine ecosystem and serve as a food source for many other animals.
Lampreys, sharks, and platypus are all vertebrates. Lampreys are jawless fish and belong to the class Agnatha. Sharks are cartilaginous fish and belong to the class Chondrichthyes. Platypus are mammals and belong to the class Mammalia.