Marine Flat Worm

Decide to do some shore macro during low tides Here's one weirder finds!

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The Polycladida represents a highly diverse clade of free-living marine turbellarian flatworms. They are known from the littoral to the sublittoral zone (extending to the deep hot vents), and many species are common from coral reefs. Only a few species are found in freshwater habitats.

Often polyclads are associated with other invertebrates, such as bivalve mollusks, sponges, corals, or ascidians. In such associations, the worms may use the invertebrates as a source of food, or they may find protection from predators inside the structural framework of these "hosts". Most polyclads hide away from direct light. However, some of the brightly colored species often are active during the day. With their flamboyant coloring they advertise their potential toxicity to visual predators such as fish.