- Arose 150 million years ago
- Chimaera, is the common name for members of any of the thirty species of deep water cartilaginous fishes related to sharks
- Subclass: Holocephalans
- Some species reach more than 2 m (6 ft) in length
- They feed on smaller animals, such as molluscs, in temperate oceans
- Scaleless skin and large eyes
- Ratfishes have long tails and poisonous spines in front of dorsal fin
