A fish with fangs?

Fangtooth
(Anoplogaster cornuta)

Looking like it just swam out of a horror movie is the amazing fangtooth. Known scientifically as Anoplogaster cornuta, this menacing creature haunts the deep waters of many of the world's oceans. The fangtooth gets its name from its rather impressive looking teeth, which are actually the largest teeth of any fish in the ocean when taken in proportion to body size. Because of its unusually grotesque appearance, the fangtooth has earned the nickname "ogrefish". It is also referred to by some as the common sabretooth.
Although the fangtooth may look like a true monster, it is actually a small fish, reaching a maximum length of only six inches (16 centimeters). It has a short, deep body and with a large head and mouth. The head contains numerous mucous cavities separated by serrated ridges. These cavities are covered over with thin skin. The body of this fish is covered with small, prickly scales, and its color varies from black to dark brown. It has very small eyes that are set high on the head. To compensate for relatively poor eyesight, the fangtooth has developed an unusually prominent lateral line which helps it to sense movement and vibration from the surrounding water.

Undoubtedly the most noticeable characteristic of this species is the teeth. They are so large that the fangs on the lower jaw actually slide into specially formed pockets in the roof of the mouth when the jaw is closed. These pockets extend into sockets on either side of the brain. These teeth become a formidable weapon as the fangtooth hunts squid other small fish. Because its eyesight is not good, many researchers think the fangtooth hunts by a process known as chemoreception, where it essentially must bump into something edible as it searches the dark waters. It is believed that these fish migrate to upper layers of the ocean to feed during the night and then return to the murky depths during the day. If a fangtooth wanders too close to the surface, it risks becoming a meal for larger fish species such as marlin or tuna.

Fangtooth reproduce by laying eggs that hatch to reveal tiny plankton-sized larvae. Their spawning frequency is not well known, although it has been observed between June and August. As the larvae eventually grow into the juvenile stage, they look completely different from the adults. They are light gray in color with long spines on their heads. They also have larger eyes and slightly smaller teeth. This difference in appearance initially caused scientists to assume that it was a different species entirely. Unlike the adults, the juveniles feed by filtering plankton from the water using specially formed gill rakes. These gill rakes disappear as they reach maturity. The juveniles begin to resemble the adults when they reach a size of about three inches. At this time they begin to descend down to deeper waters. Scientists still do not know how long they live.

The fangtooth is found throughout the world in temperate and tropical ocean regions including the waters off the coast of Australia. It is one of the deepest living fish species yet discovered. These fish are commonly seen between 600 and 6,500 feet (200 - 2,000 meters), but have been observed as deep as 16,000 feet (5,000 meters). The pressure at these great depths is intense and the water temperature is near freezing. The fangtooth is more robust than other deep water species. Researchers have been able to keep them alive for months in captivity in spite of the vast differences in temperature and pressure.

Source: http://www.seasky.org/deep-sea/fangtooth.html

Yikes!