Class Cephalospidomorphi (Phylum Chordata)
Examples and Traits
Class Cephalospidomorphi has thirty five species, and is home to the Lamprey, which are parasites. they have a more developed skull, and no jaw. They have no paired fins. Their skeletons are made of cartilage and they retain their notochord. Cartilage pipes protect their dorsal hollow nerve ending. They have kidneys and gills. They reproduce sexually with external fertilization and with separate sexes. They have a closed circulatory system, as do all vertibrates. Lamprey and Hagfish, as well as all fish, have a two chambered heart.