Eulimidae is a family of very small parasitic sea snails, marine gastropod mollusks in the superfamily Eulimoidea.
These small parasitic snails live on (or in some cases in) the bodies of echinoderms such as sea cucumbers, sea urchins, sea stars, etc. The snails have a proboscis which they extend into their host's body cavity in order to feed.
Read more about Eulimidae: Genera