Our tiny dive boat bobs on the crystal blue Flores Sea, about a mile from the primitive Indonesian villages along the shore. I tighten my fins, swig a few test gulps of air through my scuba gear and am about to roll in. Suddenly, a black beast the size of a minivan explodes out of the water. The enormous splash rocks the boat. "Manta ray," our divemaster says. "They're showing off. Like puppies. Okay. Now you, jump in."

Underwater, no one can see you sweat. I shrug, roll into the water and descend through schools of neon and Technicolor reef fish into the coral jungle. The weird growths, the psychedelic formations-giant corals, some like moose antlers, some flaming red with spikes, some like brains-make for a surreal scene. It's like swimming into a Dal painting.

I float over to a couple of big groupers. They're the size of large dogs. As I watch, three or four miniature, delicate "cleaner" shrimp hop fearlessly into the mouth and gills of the first fish, who waits politely for his cleaning. It's a little like a car wash. Then there's the boxer crab, whose front claws appear clad in big white boxing gloves-which turn out to be two fluffy white sea anemones. The crab carries these poisonous creatures constantly, jabbing them at prey like an aquatic Muhammad Ali.

Even the most seasoned divers are overwhelmed by the parade of bizarre life forms that dwell in the reefs. In the face of such dazzling beauty, it is shattering to realize that the world's coral paradises are perishing at an alarming rate. Almost 100,000 square kilometers of reefs have died; experts estimate that within a few decades, 60 percent of the reefs will be dead. No doubt, extraordinary species are being extinguished even before they've been discovered. It made me wonder: who's keeping tabs on this?