Sacoglossans are a species of sea slug known for their amazing colors and patterns. Elysia chlorotica, a Sacoglossan that lives beneath shallow waters on the East coast is known for something else: this slug feeds on algae, and instead of breaking down the plant completely, they suck out the cells and use them to photosynthesize.
This process is called “kleptoplasty,” and it enables the slug to power itself with energy from the sun. To use the cells, the slug must first find some Vaucheria litorea, the type of algae it eats. Then it sticks it’s radula into the plant and sucks out the inside contents. The slug breaks down everything but the chloroplasts, which it stores for later. Then, the creature can spread out and wait for it’s food from the sun. Elysia chlorotica also takes the green color from the chloroplasts to camouflage themselves, giving them a leaf-like appearance.