👉 Gracilopterygian is a family of fish in the order Echinodermata, which includes a wide range of species known for their unique adaptations that allow them to thrive in various environments, such as rocky coastlines and saltwater habitats. Some examples include the popular "Moby Dick" character, Gracilopterygian whales, which are characterized by their large size, streamlined bodies, and ability to swim long distances at high speeds.