Nudibranchs: Beauty of the Sea

Hypselodoris edenticulata: Florida Regal Sea Goddess

Okay, normally I would put these links and outside references at the end of the post, but there are so many beautiful pictures that you should REALLY look at that I am putting them right here for your convenience, so that no one is scared away by the long post itself.

More Pictures And Awesomeness!!
The Sea Slug Forum 
NudiPixel
National Geographic Nudibranch Gallery (David Doubilet)
Blue Dragon Pictures (Flickr--paulhypnos)
Nudibranch Gallery (Sergey Parinov)
The Right Blue


Now, on to the post! Pretty Sea Slugs!!
 Nudibranchs are shell-less mollusks upon which nature has decided to paint in pretty much every color imaginable. But these jelly-like sea slugs aren't just beautiful; with a spectrum of hues and adaptations, nudibranchs are masters of incorporating what they eat into their own bodies.

Halgerda terramtuentis: Gold lace nudibranch

If you're a nudibranch, you really are what you eat. They are carnivores that graze on everything from algae, sponges, and corals to anemones, barnacles, hydroids, and even other nudibranchs. Their color and their very survival is often derived from what they eat.

Many incorporate pigments from the coral they eat into their bodies, resulting in effective camouflage. Some can even store chloroplast in their outer membranes and let these chemical factories make sugar for them. Others instead incorporate the nematocysts (stinging cells) of jellyfish, hydroids, anemones, and other nudibranchs into the cerata (dorsal body wall) and use brighter colors to warn predators of their toxicity.

Glaucus atlanticus: Kinda looks like a Pokemon

Glaucus atlanticus (sea swallow), feeds on siphonophores like the deadly Portuguese Man o' War, collecting the stinging nematocysts in their feathery cerata. In fact, their sting is even worse than the original, because they appear to store the worst ones in high concentration. Beautiful but scary. o_O

Hexabranchus sanguineus: I whip my dress back and forth

Hexabranchus sanguineus is called the Spanish dancer for its beautiful red and white body and the fluttering dance-like swimming it exhibits, looking for all the world like a flamenco dancer's dress. Most nudibranchs chill out at the bottom of the sea, but the Spanish dancer swims freely. :)

Pteraeolidia ianthina: Great Blue Sun Dragon!!!

Pteraeolidia ianthina, otherwise known as the blue dragon, is solar powered! Yes, it's an animal, not a plant. Yes, it's blue. But just under that beautiful blue are green-brown zooxanthellae (microscopic plants), which it acquires as a juvenile form by nomming on hydroids. After it's developed enough, it can go quite a while without feeding, just subsisting on the sugars that the zooxanthellae provide in exchange for a sweet place to live.

Images:
Scuba Diving Magazine: Regal Goddess (Douglas Kahle)
The Right Blue: Gold Lace
Fuck Yeah Biology: The Blue Sea Slug
The Sea Slug Forum: Blue Dragon (Sukhdev Singh)