Sea otters (Enhydra lutris) are the smallest marine mammals in the world. We distinguish three subspecies: Asian sea otter, northern sea otter, and southern sea otter.
The largest subspecies is the Asian sea otter, which lives in the northwestern Pacific Ocean. The southern sea otter, which lives along the central and southern California coast, is the smallest.
The circulatory system of snails is open. This means that hemolymph (equivalent to blood) is pumped into the body cavities surrounding the internal organs.
The oxygen carrier is hemocyanin and the copper it contains. Hemocyanin is blue.
