The Rhizodus (Rhizodus hibberti) was a species of Rhizodontida that lived in England during the Carboniferous period (330-300 mya).
River Monsters[]
Prehistoric Terror[]
It appeared in River Monsters Season 7 Episode 3, "Prehistoric Terror." In the extended version of the episode, Jeremy Wade caught a lobe finned relative in Australia. He also swam in a tube in a Saltwater Crocodile's enclosure, seeing the creature close up. The Rhizodus lived in murky freshwater lakes, meaning that it was probably an ambush predator that hunted man-sized prey. The crocodile was a fairly good analog since it also is an ambush predator. However, the Rhizodus was even larger and more powerfully built than a Saltwater Crocodile. Jeremy concluded that it was the most dangerous known River Monster of all time.
Descripton[]
Rhizodus is estimated to have grown to between 19 and 23 feet, making it the largest known freshwater fish of all time. It has been extinct since the Carboniferous Period. It is represented by a fairly small number of remains, so the exact size and physiology cannot be determined for certain.