Costasiella kuroshimae are capable of a physiological process called kleptoplasty, in which they retain the chloroplasts from the algae they feed on. Absorbing the chloroplasts from algae then enables them to indirectly perform photosynthesis.[6]
And I'm pretty sure there are also jellyfish that live in symbyosis with algae that they carry along with them which photosynthesize, creating sugars for the jellyfish.
Eh, that's a few dozen steps removed. By that standard, every herbivore "uses" photosynthesis.
These guys (coral & lichen too) use photosynthesis much more directly, completely encapsulating the algea and supporting it internally. It's much closer to mitochondria.
The really interesting thing about costasiella kuroshimae is that its digestive system branches and goes up into all of those 'leaves', which is how the algae makes its way there to have its chloroplasts extracted.