So... not fighting or poison type at all? Haha. Was pretty psyched for it to be poison/something, and not just water. Although, I guess there's still hope for any of its potential evolutions.
If I remember that Pokedex list that was confirmed fake, it mentioned a possibility for a sea cucumber to evolve into an anemone, and I know that anemone tentacles can sting so maybe the Poison-type could be added to Pyukumuku's evolution.