Costasiella kuroshimae is a
species of
sacoglossan sea slug, a shell-less
marine opisthobranch gastropod mollusk in the family
Costasiellidae.
It has the ability to incorporate
chloroplasts from the
algae it feeds on into its body and use them to do
photosynthesis
https://en.wikipedia.org/wiki/Costasiella_kuroshimae