Who is small, transparent and very common in the ocean yet can not be googled?
Even with Google, if you do not know whether it is an animal or a plant, how would you search for it? How would you describe it? Plankton is Greek for wanderer. Phytoplankton is plankton consisting of microscopic plants . Zooplankton is plankton consisting of small animals and the immature stages of larger animals. That much is known about our wanderer. The crux in searching for its name lies in that it is ubiquitous, seen everywhere sometimes as dense as a snowstorm, yet most of us neither pay attention nor know what to call it.
Update:
Fortunately, the great Cory Pittman saw this post and pointed me to a few articles on larvacea. The image above is the mucous “house” of larvaceans. They are planktonic nocturnal animal that creates a gelatinuous “house” in order to feed. Their body consists of an oval trunk and a long thin tail. The “house” encase the body but not the tail of the larvacean so it may swim. It uses the house as a complex filter to catch very small particles. The filter do clog and must be discard and replaced every four hours or so.
more here:
https://en.wikipedia.org/wiki/Larvacea
https://www.earthlife.net/inverts/larvacea.html
https://www.imas.utas.edu.au/zooplankton/image-key/appendicularia