Nudibranchs

There are more than 3,000 known nudibranch species, and scientists estimate there are another 3,000 yet to be discovered. So-called Spanish dancers, like this one off the coast of New South Wales, Australia, boast some distinctions over other nudibranchs: First, they can be enormous, reaching a foot and a half (46 centimeters) long. Most nudibranchs are finger-size. Second, it can swim, a skill most of its cousins lack.



Nudibranchs are hermaphroditic, carrying both male and female reproductive organs. Mating pairs fertilize one another and lay up to two million eggs in coils, ribbons, or tangled clumps, as this purple-painted Hypselodoris is doing.


Generally oblong in shape, nudibranchs can be thick or flattened, long or short, ornately colored or drab to match their surroundings. Some max out at a quarter of an inch (6 millimeters), while others can reach a foot (30 centimeters) long or more.



Nudibranchs' unique lives and body chemistry may harbor breakthroughs that could benefit mankind. Scientists are attempting to derive pharmaceuticals from their chemical armory and get clues to learning and memory from their simple nervous systems.