I've come across a few real life creatures that seem like they'd be great bases for new Felaryan creatures. Take a look. All of these creatures are real. (Honest!)
Osedax Frankpressi:
Osedax frankpressi is a species of worm that grows exclusively on the bones of dead whales. Their microscopic eggs can be found drifting in every corner of the sea, waiting patiently to contact their highly specific food source. Once hatched, the female develops into a pinkish, flower-like animal that bores into bone with a network of spongy "roots", and digests it with the aid of a symbiotic bacteria. The males remain microscopic, and thousands may inhabit the body of a female. The worms will die when the skeleton is fully consumed, but only after pumping tens of millions of eggs into the water.
Pistol Shrimp:
The Pistol Shrimp has a specially modified claw that, when snapped shut, generates a burst of sound and air that can paralyze or even kill small prey such as fish or other shrimp.
Slickheads:
Slickheads of the genus Rouleina are coated in a "jacket" of slimy, sticky black flesh that traps any small organism that swims into it. When enough food has been caught, the fish strips off this skin and eats it.
Cleaner Wrasse:
The cleaner wrasse, a tiny blue and black reef fish, feeds by eating the parasites, dead skin and fungi off of other sea creatures who even allow the fish to swim in and out of their mouths and gills. Fish of every shape and size will actually wait patiently in a line to be groomed by the wrasse, and few if any fish (including sharks) will willingly harm one or harrass the other patients. Some blennies, however, are "false" cleaners, imitating the wrasse and feasting on the healthy flesh of unknowing patients.
Deep Ocean Anglers:
Probably the largest and most common group of the abyssal fish, deep-ocean anglers boast one of nature's most extreme examples of sexual dimorphism (physical difference between genders). The female angler (three examples shown above) is a large, bloated predator that lures prey directly into her jaws with a luminous "fishing pole". The male, however, is a tiny, eyeless creature with highly developed nostrils and very little else. Once he has sniffed out a female, he locks his jaws onto her flesh and begins to drink her blood. He will remain there for life, losing most of his non-reproductive organs as his skin and circulatory system merges with those of his mate. Some females may carry several parasitic husbands at once. It is not unheard of for a male to attach to a female of the incorrect species.
Another Type of Angler:
Anglerfish of the family Thaumaticthydae have taken the art of deep-sea fishing to its perfection with a luminous, bulb-shaped lure hanging directly from the underside of the upper jaw, which folds shut along its length like the leaves of a carnivorous plant. Once the prey is trapped, the smaller, lower jaw opens to create a vacuum.