Isn't that an actual species of lobster? I remember seeing it on the news or discovery channel or something.
-edit-
I did a little searching and found
"A lobsterman in Maine caught a very rare two-tone lobster this week. The little critter was split right down the middle, with one half a typical greenish color and the other half a bright red tone. The odds of finding such a lobster are between 1 in 50 million and 1 in 100 million. The reason that such an unusual color scheme is even possible is that each side of a lobster actually develops independently; in this case, one side simply lacked the blue pigment that would have darkened the red side"