I'm sure some of you are thinking, "The heck are you getting at?" So I'll explain.
Lets look at how battle sprites forms are made. The game says they adapt to their environment causing them to change thus saying where they are made them who they are. If we look at the Draco we can assume sense it was a fire level and the most common form of constructions were red rovers that it adapted to be similar to red rovers.
Now lets look at the Seraphynx.
It is a cat with wings that was found in a library section of a haunted train station full of undead enemies. So how does this look like a owlit? or even have to do with owlits? Well looks at the drops of zombies and spookats.
They both drop owlit feathers. This means that the undead family has the closest connections to owlits then any family of monster in this game. The only reasonable connection to draw here is that the skeletons are the bodies of the owlits and the mewkats are the souls.
"But WWC the mewkats are well, cats. Wouldn't the Owlits be more like owls?"
Not necessarily. The spookats and spheraynx both have wings. This could explain where the feathers are from. They could be owl/cat/human hybrids. The body of people, the wings of owls, and the fur/tail/head of cats.
How creepped out are you no knowing your cute little cat is the closest thing we have to a dead race of people who for all we can tell died to their own intellect?
I believe that the Kat Tribe stormed and killed all the Owlites. If need be, refer to the items introduced in the Kataclysmic Confrontation. (Black Kat Cowl, Kat Claw Cowl, etc.)
I wouldn't be surprised if the dust zombies were somehow related to the Owlites, but before the new loot update, only kats dropped owlite feathers. I mean, slimes drop driftwood as of the moment, so going by materials isn't all that effective.