"Stunningly beautiful but deadly," the Gulf of Mexico's Venus flytrap anemone (pictured) acts much like its terrestrial namesake, stinging its prey with an array of tentacles, according to the U.S. Geological Survey. (See pictures of more stinging and toxic sea creatures.)
The species' native Gulf—along with the Mediterranean Sea, Chinese waters, the Baltic Sea, and the Caribbean Sea—are the ocean regions most under threat from human activities, according to Census of Marine Life scientists.
For instance, nutrients in sewage and fertilizer washed from the land are degrading these marine habitats by creating oxygen-free "dead zones," the report says.
What's more, the Gulf of Mexico oil spill may worsen these dead zones, as well as wield untold damage to the animals at the bottom of the food chain.