I decided to make a new genus based off my sona Khaluo, just so I don’t have to explain the weird features! I am pretty sure this is the first time anybody has had on original genus instead of just a species! Vote below on the openness of the species as I explain the lore!

Cetris live in the distant future, millions of years after humans have gone extinct. Sharks, who have been on Earth for billions of years by this point, are some of the few survivors of what is known to the cetris as “the C-G Mass Extinction”. They don’t know how it was caused, only that all the terrestrial life died out some 100 million years before their earliest shark ancestors began filling the open niches.
It is unclear how, as more fossils of ancient life are discovered, but a distant relative of all cetris groups crawled onto land and discovered the ruins of ancient civilizations, long abandoned. Over time, the groups diversified into several species of “land sharks”, with most if not all gaining the ability to stand upright as the curious fossils of “the ancient ones” did. They began to hunt and develop complex social structures, heavily built around nature in a way few ancient ones are speculated to have been.
Now, the groups have become well adapted to their respective landscapes.
The first and oldest group, known as the Quill, live in the mountains around ancient lakes. Fish are still a major part of their diet, and they have an extremely complex matriarchal society.
The second eldest, the Nault, live in dens and caves. Their eyes are well adapted to the darkness and they have bioluminescent eyes and features that help them thrive in the cold darkness below. They burrow deep into the Earth and eat small cave creatures that run around their feet. They have a system based off of challenges, and 50 possible leaders are selected to run through said challenges in order to win. Sort of a “whittle it down” system as opposed to the Quill’s way of “Is she strong and also a she?”
Third on the list, halfway down, are the Arials. They make their homes in treetops or craggy cliffs and have adapted their upper limbs to have feathery structures for flight. As it is often quite cold, mountaintop Arials will have more fluff than their smooth, sleek tropical relatives. These often live solo, with their mates, or in family groups without one leader. Though they do often get together and vote on a representative to go the meetings of the High Council.
Fourth is the Seanarians, who readapted for life in and around the water. Their homes are often on the beach or under the waves and they eat mostly fish and small animals. They have a simple leadership structure, where one family merely has to brute force their way on top.
Fifth are the Woodleds, and they prefer woodland and forested areas as their homes. They build treehouses or ground dwellings and prefer a more omnivorous diet. They lead with kindness and a democratic style; the leader makes important decisions about the options and goes to meetings, but really the citizens are in control.
The sixth and final group, the Firies, are unique. They choose to live in volcanoes and have the ability to create fire by opening their paws. Their lives are based around fire, and they use it for light, food, and even religious ceremonies. One family leads, and can be overthrown at any point. They use their tails to swim through and collect lava and fire.

Note that all still have shark-like tails, but some use them more for gliding and steering as well as weight balance than swimming.

I hope you enjoyed the lore, make sure to comment with where you want to see it go as well as how open it is! By that, I mean open, semi-open, or closed! Thanks!