The Weirdest Sea Creatures You've Ever Seen

So what's really down there? Down as in way down below the ocean, as Donovon sang in 1968. According to the latest Census of Marine Life, we're starting to get a clear idea.

On Monday, scientists released a preliminary inventory of ocean species distribution and diversity in 25 biologically representative regions from the Antarctic to the Arctic. Their final report will get released early next month.

Before the decade-long census gets revealed, the researchers dropped a few morsels for us to chew on. For instance, the waters off the coasts off Australia, Japan, China, the Mediterranean Sea and the Gulf of Mexico are the world's most diverse in terms of known species.

When the census gets released in London, it's expected to report there are more than 230,000 marine species in the world's oceans. Even more intriguing, the preliminary inventory released on Monday noted that "for every marine species of all kinds known to science, census scientists estimate that at least four have yet to be discovered." That makes for a lot of fish. And probably a lot of fish in shapes, sizes and colors that will blow our minds.

"At the end of the Census of Marine Life, most ocean organisms still remain nameless and their numbers unknown," says biologist Nancy Knowlton of the Smithsonian Institution. "This is not an admission of failure. The ocean is simply so vast that, after 10 years of hard work, we still have only snapshots, though sometimes detailed, of what the sea contains. But it is an important and impressive start."

The census is issuing early looks at some of these marine species, and you can check out a sample of what they discovered in the accompanying image gallery.