Dalakoalt, "swamp serpents" originate from Qiadiorah, with the first of them appearing during the first 10 years of the Bionic Ages. They are often said to be the children of Taakakoalt, a serpent Goddess of the Qiadioran pantheon. They are a particularly common folk around Qiadioran marshlands.
Mesuquiti, "cobra people" on the other hand originate from Muejasa, first of them appearing a few years after the Dalakoatl. Their reputation is generally mixed, mostly associated with their lethal venom and Apophis. As you see, these Animalus are rather recent-ish compared to the others. These first years of the Bionic Ages are often called "The Serpentine Dominion".
They only have a slight size difference from their feral brethren, no other major evolving trait has been documented. They haven't grown limbs. Yet.
Due to this slight size difference, they are commonly mistaken as wild snakes when noticed from far away. This has resulted in a few casualties; having an arrow or bullet shot into their head from a misunderstanding. The snakefolk being limbless doesn't mean they are any less capable than the average fleshwalker. They've managed to adapt to this, using their tails and jaws as tools. Their tails have evolved to be stronger and more flexible, allowing them to manipulate objects as if it was an arm. Though they also use attachments on their tails for easier work, for example, hooks or prosthetic hands