Glowgill

The glowgill split from its ancestor, the gillrom. The lower competition in deeper waters attracted some, and they became increasingly adapted to deeper waters. The scarcity of photosynthetic microbes led them to also incorporate detritus into their diet. The two pairs of feelers on the front of the body became better at drawing microbes and debris into its mouth. In the low light, its purple color has faded slowly to be more gray. On the ends of feelers and along gill slits, symbiotic colonies of bioluminescent microbes grow, although they are somewhat faint. A fourth pair of gills evolved due to less oxygen in the deep water.

By day, they feed in the upper twilight zone on photosynthetic microbes. By night, they venture deeper for detritus and safety from predators. This addition to their diet and lack of competition has caused them to grow slightly in size.