Vampire (Armatus) Tetra (Hydrolycus armatus)

Those fangs aren't an exaggeration, the lower jaw carries two genuinely oversized canines long enough that the upper jaw has evolved a pair of sockets just to let the mouth close around them without stabbing the roof of its own mouth. It's a predatory characin built for fast midwater strikes on smaller fish, not a peaceful community schooler, so tankmates need real size and speed to stay off the menu. A genuinely fascinating oddball for anyone building a predator-focused freshwater tank.

Care level: Moderate · Temperament: Semi-aggressive, predatory to small fish · Max size: ~14" · Min tank: 180+ gal · Diet: Carnivore, live/frozen foods