06088 - Beautiful 1.37 Inch Juvenile Onchopristis numidus Cretaceous Sawfish Rostral Tooth

 Impressive well preserved Onchopristis tooth. Not restored or glued.

Onchopristis is a genus of extinct giant sawfish that lived in the Lower Cretaceous to Upper Cretaceous in North Africa and New Zealand. It had an elongated snout lined laterally with barbed teeth. It is a large sawfish, known from remains throughout North America, North Africa and New Zealand. It was very large, up to 8 m (26.2 ft) long when fully grown. As with modern sawfish, Onchopristis's eyes were on top of its head, to spot predators rather than prey, and its mouth and gills were under its body. The rostrum, or snout, was around 2.5 m (8.2 ft) long, lined with barbed teeth. In the type species, O. numidus, each tooth had one barb, but in O. dunklei there were two to five barbs on each tooth, two to three in O. d. praecursor, and three to five in O. d. dunklei. The rostrum most likely would have had electrosensors to detect food in the water below them like most modern sharks and some rays. Onchopristis may have raked through the riverbed to find and then eat prey.
 
This taxon was described by Hauq (1905) and belongs to the Pristidae family. Their fossils are a good indicator of paleoenvironments related with deltas and estuaries. This type of fish constituted a big part of the diet of the great ichthyophagous coetaneous dinosaurs, such as the Spinosaurus.