Nudibranquios (Nudibranch)

• A nudibranch /ˈnjuːdɨbræŋk/ is a member of Nudibranchia, a group of soft-bodied, maaldogalanterine gastropod mollusks which shed their shell after their larval stage. They are noted for their often extraordinary colors and striking forms. There are more than 3,000 described species of nudibranchs.
• The word "nudibranch" comes from the Latin nudus, naked, and the Greek βραγχια, brankhia, gills.
• Nudibranchs are often casually called sea slugs, but many sea slugs belong to several taxonomic groups which are not closely related to nudibranchs. A number of these other sea slugs, such as the colorful Aglajidae, are often confused with nudibranchs. 
• This group includes some of the most colorful creatures on earth. In the course of their evolution, nudibranchs have lost their shell while developing alternative defense mechanisms. Some species evolved an external anatomy with textures and colors that mimicked surrounding sessile invertebrate animals (often their prey sponges or soft corals) to avoid predators (see camouflage). Other nudibranchs, as seen especially well on chromodorids, have an intensely bright and contrasting color pattern that makes them especially conspicuous in their surroundings. This is believed to be an example of aposematic coloration; the shocking coloration warns potential predators that the slugs are distasteful or poisonous.