| That makes Helicoprion a distant relative of today's rabbitfish, ratfish and other chimaeras. |
| The feature was previously unknown in sharks and other chondrichthyans, an order of fish whose modern descendants include sharks, skates, rays, and chimaeras. |
| Like those distant relatives, chimaeras have skeletons of cartilage, not bone. |
| Cartilaginous fishes include sharks, rays, skates and chimaeras. |
| In the living chimaeras, Callorhinchus and Chimaera, the authors were able to show the persisting boundaries between the individual teeth. |
