This undated image provided by Bugwood.org shows a hammerhead worm on a leaf in India. The narrow, snakelike flatworm has a head built like that of a hammerhead shark. (Arun T.P./Bugwood.org via AP) ...

If you've ever had the misfortune of seeing a hammerhead worm, you'd know about it. These unique little creatures look like someone crossed your classic earthworm with the top of a hammerhead shark.

Michael Raupp is a bug guy. MICHAEL RAUPP: I try to demystify the lives of invertebrates, particularly insects. SIMON: He's professor emeritus in the Department of Etymology at the University of ...

They're technically not 'worms' as we know it, but rather, planarians. The hammerheads were most likely introduced to the U.S. in 1891 and thought to have come from southeast Asia. The first reports ...