Rostral bones
The rostral bone (rostral) is a group of the dinosaur in the Ceratopsia existing bone at the tip of the upper jaw . It is an unpaired bone lying in front of the intermaxillary bone and represents perhaps the most striking synapomorphism of Ceratopsia.
Particularly in the more developed Neoceratopsia the rostral bone is shaped keel and pointed forward, forming the counterpart to the all Vogelbeck dinosaurs existing before dental mandibular located predentary . The hook-shaped rostral bone reached over the also pointed predentale and thus provided the typical parrot-beak-like snout (rostrum) of these animals. This tall, narrow beak differed from the round, broad beaks of most other bird pelvic dinosaurs and allowed for very selective feeding.
The rostral bone of the Ceratopsia is not to be confused with the trunk bone (Os rostrale) of the pigs as well as the rostral shield (Scutum rostrale) at the tip of the snake snout and the small ones Mosaic bones in the snout regions of the fish (also: Rostral series).
literature
- Wilfried Westheide , Reinhard Rieger (Hrsg.): Special zoology. Part 2: vertebrates or skulls . Spektrum Akademischer Verlag, Heidelberg / Berlin 2004, ISBN 3-8274-0307-3 , pp. 401-402.
- David Fastovsky, David Weishampel : The Evolution and Extinction of the Dinosaurs . Cambridge University Press, Cambridge 2005, ISBN 0-521-81172-4 .
Individual evidence
- ↑ Rostral. In: Ulrich Lehmann : Paleontological dictionary . 4th edition. Ferdinand Enke Verlag, Stuttgart 1996, ISBN 3-432-83574-4 , pp. 206 .