Phantomstars
Dwelling within the deep dark of the ocean depths, the phantomstars split from their ancestor and flourished, growing in both overall numbers and species. Like their cousins, the Filterbunnies, they make up a large part of the ocean's microbiota. However, instead of living within the substrate, the phantomstars take up the role of zooplankton. Free-floating in the pitch black waters, their nearly translucent bodies make them very difficult to detect, save for their "intestines" when laden with food. Their internal anatomy is very similar to that of their ancestors, with the innards dominated by their "intestines" and muscles, and an anus at the end of one of their arms. One notable difference, though, is that the length of their baits have increased even further, an adaptation that makes them more efficient at filter-feeding.
While they will feed on smaller microorganisms or latch onto and scavenge the occasional sinking corpse, a good portion of the diet of phantomstars is composed of marine snow and other bits of sinking organic matter. As these bits of detritus sink down from the surface, they are consumed by a variety of deep sea life, including these ones. When these in turn die or are eaten by larger organisms, the nutrients will either make their way to the abyssal plain or be returned to the surface with either upwelling currents or deep-diving surface species. Such is the cycle of life in the ocean.