From Live Science, via MSNBC: Half plant, Half slug.
"The sea slugs live in salt marshes in New England and Canada. In addition to burglarizing the genes needed to make the green pigment chlorophyll, the slugs also steal tiny cell parts called chloroplasts, which they use to conduct photosynthesis. The chloroplasts use the chlorophyl to convert sunlight into energy, just as plants do, eliminating the need to eat food to gain energy. " photo Credit: Nicholas E. Curtis and Ray Martinez
So here's the plot: Swamp Slug, a benign, shy... beneficial creature may just hold the evolutionary key to cleaning up our toxic waste and saving humans from oil dependence. If only we can save them from being eradicated by the swarms of killer Fishzillas! Enter a team of heroic scientists turned reluctant heroes who try to enlist the help of a grizzly, gruff, guilt-ridden alcoholic world champion fisherman who is trying to drown his sorrows over a loved one drowned when their boat was capsized by Fishzillas (maybe he's the one who introduced the species to Maryland to begin with....ooohh.). Throw in a loyal yellow dog and a cute kid and voila! Instant B movie. It can end with the grizzly old fisherman being genetically assimilated by the slugs and becoming the first photosynthetically capable merman.
I'll tell you where to send the royalty checks.