Art by Tortoiseman
Nathairsiorcs (squaloraduloidea) are a superfamily of shark found in the Atlantic and Indian oceans. They are descended from small-spotted catsharks. They come in a dark yellow and have green spots and measure in at 4.5 feet in length.
Nathairsiorcs have a diet consisting of small squid and small fish. The only problem with their diet is that their prey are very slippery, very fast, and too large to easily fit in their mouths. The solution they developed is to have 2 mandibles to grab and manipulate prey easier. The thin bridge of cartilage in the center of the jaw has completely disappeared and left behind 2 jaws connected by a elastic tendon. The jaws can't move independently of one another but they can open and close diagonally as well as up and down. When they hunt, their facial muscles shoot out all of the jaws at once and snatch their prey from the water. They use their jaws to push their food further into their mouth and prevent it from escaping.
Their sharp teeth are solely for holding onto their prey. The teeth that they use for chewing are small cover the entire mouth and are developed from the dermal denticles. Just like their regular teeth, their mouth sandpaper replaces itself as to not be worn down. The rapid sweeping diagonal chewing of the jaw grinds down the meat into small, easy to swallow shreds.
In terms of behavior they live a fast-paced solitary life. They only meet up with each other for mating. When it comes time for the mother to lay her eggs, she will find a rocky crevice and attach her eggs there. The eggs are 3 inches long and covered in spines. As the mermaid purses develop, the mother will stay in the area to prevent any predators from getting to them.