One Just Gotta Love Them - Magnificent Nudibranch
If you consider yourself as a muck diving weirdo, than I’m positve somewhere between the top 10 macro species of your list is surely a spot for the magnificent Nudibranch. The variation of this species is basically incredible with fluorescent colours, flamboyantly displayed gills and striking forms. The term Nudibranch derives from the Latin word nudi as in exposed (I guess it has the same meaning like beeing “nudi” on a nude beach) and branch what refers to gills many times pointing out of the nudibranch body and reminding us of tree branches. There are over three thousand identified species with new findings every year and I am sure you must have had that feeling of seeing one nobody could not have possibly seen before. Well one never know but camera is good helper with a great ability to silence even the strongest sceptics. Many of the nudibranchs after the years of evolution have lost their shells, some developed poisonous defensive mechanisms, but the most of them are not poisonous at all and only mimic other poisonous family members which sends a clear signal to potential hungry predator to rather keep away.
Everything needs to move and so the Nudibranchs which covers the distances on a flat broad muscle called a foot and leaves a slimy trail. This is probably the reason why we mostly find them on the ocean floor, fairly the animal would not travel far walking with the slimy foot in the open water. But nature as always has its exceptions and there are some nudibranchs with ability to swim short distances in the water column by flexing their muscles. Sure you have heard of Spanish Dancer, right? While it's obviously perfectly suitable to what a nudibranch needs to do in life, their vision is lacklustre compared to our standards. They can see light and dark, but unfortunately not their own brilliant coloration, so basically there is no way they would developed narcissistic personality and they remain very friendly and not too cocky despite the beauty. I’m sure every photographer is well aware of it as you never see nudibranch running away from your camera or giving a sings of being bothered by blindingly strong external strobe. Obviously with their limited vision, their sense of the world is obtained through their rhinophores on top of the head and oral tentacles near the “mouth”.
Nudibranchs eat using a radula. They are carnivorous as they prey on sponges, coral, anemones, hydroids, barnacles, fish eggs, sea slugs, and other fellow family members. Nudibranchs get their bright colours from the food they eat which makes them very picky eaters and when I say picky I definitely mean it. There are individual species or families of nudibranchs which may eat only one kind of prey. The most amazing fact about nudibranchs for me is that some of them are solar powered. Few species are able to harbour green algae's chloroplasts into their bodies where they do photosynthesis using the sun and provide nutrients to sustain the nudibranch for months. Just imagine sunbathing would be from time to time the only think you would have to do to stay alive. Traveling would be again little cheaper.