Treasures of the sea

A nudibranch /ˈnjuːdɨbræŋk/ is a member of the Nudibranchia, a group of soft-bodied, marine gastropod mollusks which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms. Currently, about 2,300 valid species of nudibranchs are known.

The word "nudibranch" comes from the Latin nudus, naked, and the Greek βραγχια, brankhia, gills.
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