Day 7 comes with the intriguing looking jurassic fish, Hybodus. Though they share a common ancestry, these fish are not actually true sharks, visually similar as they may be. Aside from that though, I don't really have much more info about these creatures. I can't find much on their habitats personally, but maybe I'm just not looking hard enough. Regardless, I'm gonna use this lack of knowledge as an opportunity to take some creative liberty with the ecology of this creature within the context of the world-building thing I'm doing with this prompt list. I've given it very bright colours because I imagine these being reef hunters. They are only 2 meters in length, so they could probably hunt in and around the open parts of the reef, it's bright colours serving as camouflage against the coral.

These creatures, known as Hybodus, are predators similar to the Birgeria, however the Hybodus are more irritable. They are swift and maneuverable, able to chase down prey across the reefs they inhabit, their bright colouring letting them hide amongst the coral and wait until just the last minute to strike with a burst of speed. They are far more willing to attack people due to being rather skittish, so caution is definitely a top priority should you find yourself faced with one. Fierce hunters they may be, but invincible they are not, the ocean is home to absolutely colossal beasts and even the reefs contain creatures that would easily turn a Hybodus into a meal. They possess sharp, serrated spines protruding from their fins for the purpose of defense against such predators, and it seems to be effective enough, with populations being steady across their tropical homes. People rarely use them as a resource such as for food made using their dorsal fins, but dishes like these are only really eaten by the wealthy, and are more a sign of status rather than legitimate nutrition, and given that more often than not the rest of the fish is completely wasted, this process is rightly frowned upon.