It's official: river carnivores deserve to be high-octane nightmare fuel. Piranhas are downright terrifying thanks to their reported ability to strip a cow to the bone in seconds, and anacondas occasionally get the limelight, but most aquatic terror comes from something in an ocean or lake.
Observant individuals probably noticed the Baiji's strange facial proportions for a dolphin. Were it not nigh-extinct, the Baiji could easily make for a dolphin monster in a horror movie. It looks that far away from the playful dolphins that, even though they rape and murder people, we all know and love anyways.
Now imagine those snout proportions on a much less amiable crocodilian.
The gharial (Gavialis gangeticus) has a very long nose/mouth filled with lots of slender, sharp teeth, just like a river dolphin. It is native to India and is one of the few extant members of the family Gavialidae. It is one of the largest crocodilians at 5 meters in length and 650 kg. With that snout, a history dating almost all the way back to the dinosaurs, and the tanklike build of a large crocodilian, this has to be a real monster, right?
Gharials are harmless to humans, actually. The same weird-looking jaws that the river dolphin has make it impossible for the gharial to consume something as large as a human. Unlike other crocodilians, they also move poorly on land. Reports of gharials eating humans come from either a) the gharial's habit of swallowing stones and jewelry to aid its digestion or b) misidentification with other crocodilians. India has three different types of crocodiles, after all.
Besides an interesting evolutionary history, the gharial also has one very important trait that sets it apart from other crocs: They are the only visibly sexually dimorphic crocodilian. The males have a bulges above their nostrils called ghara ("pot") that gives the gharial its name. Not only is the pot-shaped growth attractive to female gharials, it helps the male breathe underwater and blow bubbles as part of its mating rite.
A crocodilian that blows bubbles. No wonder most of them are extinct.