Name: Sarcastic fringehead (Neoclinus blanchardi)
Region: They are found in the Pacific, off the coast of North America, from San Francisco, California, to central Baja California and their depth range is from 3 to 73 metres (9.8 to 240 ft).
Risk of Extinction: No info.
More Info: Pugnacious and aggressive, these fish lie in wait in their shelters ready to attack prey or intruders. With only a bizarre-appearing head protruding from the shelter, an enormous mouth, and needle-like teeth, they are ready to aggressively defend their territory against all intruders. They are known to attack almost anything (including divers)that appears anywhere within their range of vision. They show who’s boss with an intimidating, animated threat display complete with body and head flexing, spreading gill covers, and snapping jaws. If the threat does not solve the problem, it is usually followed by a vicious, gaping-mouth attack on the intruder and a hot pursuit.
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(photo taken from http://www.realmonstrosities.com/2012/05/sarcastic-fringehead.html