A Spanish shawl nudibranch (Flabellina iodinea) photographed at Research Experience and Education Facility at the University of California, Santa Barbara
A Spanish shawl nudibranch (Flabellina iodinea) photographed at Research Experience and Education Facility at the University of California, Santa Barbara
Photograph by Joel Sartore, National Geographic Photo Ark

Nudibranchs

Common Name:
Nudibranchs
Scientific Name:
Nudibranchia
Type:
Invertebrates
Diet:
Carnivore
Average Life Span In The Wild:
Up to 1 years
Size:
0.25 to 12 inches
Weight:
Up to 3.3 pounds

The bottom-dwelling, jelly-bodied nudibranch (NEW-dih-bronk) might seem an unlikely canvas for Mother Nature to express her wildest indulgences of color and form. But these shell-less mollusks, part of the sea slug family, bear some of the most fascinating shapes, sumptuous hues, and intricate patterns of any animal

Population

There are more than 2,000 known species of nudibranch, and new ones are being identified almost daily. They are found throughout the world's oceans, but are most abundant in shallow, tropical waters. Their scientific name, Nudibranchia, means naked gills, and describes the feathery gills and horns that most wear on their backs.

Characteristics

Generally oblong in shape, nudibranchs can be thick or flattened, long or short, ornately colored or drab to match their surroundings. They can grow as small as 0.25 inches or as large as 12 inches long.

Behavior

They are carnivores that slowly ply their range grazing on algae, sponges, anemones, corals, barnacles, and even other nudibranchs. To identify prey, they have two highly sensitive tentacles, called rhinophores, located on top of their heads. Nudibranchs derive their coloring from the food they eat, which helps in camouflage, and some even retain the foul-tasting poisons of their prey and secrete them as a defense against predators.

Nudibranchs are simultaneous hermaphrodites, and can mate with any other mature member of their species. Their lifespan varies widely, with some living less than a month, and others living up to one year.

This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
Photograph by Yaroslav Trukhanov, National Geographic Your Shot

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