A Baltic Sea Nudibranch

A reddish-orange nudibranch.
© OCEANA Carlos Minguell

Nudibranchs are mollusks that have evolved from shelled ancestors. Like the reddish-orange Coryphella verrucosa shown here, they're often noted for their vibrant colors and striking forms. View other images of Baltic Sea life in photo gallery of Oceana’s 2011 expedition.