Blobfish

This unique and somewhat disgusting looking fish is rarely seen by humans. The reason for this is that it lives at a depth where the pressure is several dozen times higher than the pressure at sea level. This makes it very difficult for humans to visit or even survive. The blob fish is basically a gelatinous mass with a density that is only slightly less than water. This gives in buoyancy that allows it to float just above the sea floor without expending energy to swim.