Nudibranchs (also known as sea slugs) are a type of shell-less mollusk in class Gastropoda that are often equipped with vividly bright colors. They cannot see the colors themselves, however; they can only see light and dark. They are an incredibly diverse group with over 3000 different species, and live anywhere from the intertidal to the deep sea. Sea slugs eat using something called a radula, which is a toothed structure that is used to scrape prey from the rocks that they are clinging to. They have been known to be somewhat picky about their diet – certain nudibranchs may only eat certain types of prey, despite being carnivorous creatures. Nudibranchs can be anywhere from microscopic in size to 1.5 feet in length, and their lifespan varies from a few weeks to a year.
Very little is known about deep-sea nudibranchs, as they are very different to find and study at extreme depths. These deep-sea nudibranchs were found on a few dives at Axial Seamount; the species in these photos are currently unidentified.
Kennedy, J. (2019, December 13). Astounding nudibranch facts. ThoughtCo. Retrieved December 13, 2021, from https://www.thoughtco.com/facts-about-nudibranchs-2291859.