Name: Ocegressusaurus maximus
Time period: Late cretaceous
Name: Ocegressusaurus Maximus
Time period: Late Cretaceous
Origin: North America
Habitat: Shallow seas
Size: 18 m.
Longevity: 80 years or more
Ocegressusaurus is one of the very few aquatic dinosaurs of the cretaceous, but is by far the largest. This dinosaur, after millions upon millions of years of evolution, has become almost entirely aquatic, spending up to 95% of its life in the ocean and holding its breath for hours on end. The front limbs have become fully functional flippers for steering, as the hands and arms are not necessary for terrestrial locomotion in young. The animals legs however have changed comparatively little. It has webbing between its toes, and the dinosaurs hallux (the first small toe on the foot) has grown to about the size of the rest of the toes, allowing it to have more webbing. The legs have also gotten much smaller, no longer needing to support its massive bulk, and its tail has lengthened and grown much more paddle like, allowing it to propulse itself forward with great speed. One of the reasons the dinosaur has not dis-adapted its feet altogether is that, much like a hippopotamus, it primarily will walk along the bottom in order to save a significant amount of energy. The animal also has an incredible sense of smell, able to smell prey from miles upon miles away. It is one of the top predators in its area, fearing nothing other then another ocegressusaurus, but such a lofty spot on the food chain requires a massive amount of food. These animals are very territorial, and will attack anything that seems a threat, whether it is another ocegressusaurus or other aquatic predator.
The reproductive cycle of this animal, despite it being huge and majestic, is quirky at best. Because ocegressusaurus is a dinosaur, it lays eggs unlike most aquatic reptiles. A pregnant female, often accompanied by many other females, travel their way to a large uninhabited island far from shore. This is where having legs is a relative convenience. Once they get to the shore, they awkwardly crawl up the beach on their stomach using their flippers and legs, a fairly long process. Once they are far enough from the ocean, they instinctively dig a small hole and lay 5 to 10 eggs, each about the size of a grapefruit. While their terrestrial counterparts are caring parents, staying with the young after birth, the ocegressusaurus cannot afford to be. Due to its massive bulk, the animal can only be on land for a fairly short amount of time (around 8 hours) before their mass begins to ware them out, slowly suffocating them. Once the eggs have been laid, the females quickly sprawl their way back into the ocean, leaving the babies to their fate. After about 3 months, the surviving eggs hatch, generally at nighttime. At this stage of their live the babies have fairly long legs and can walk within minutes. At this point, the nymphs (named after the larvae of dragon flies, which follow an opposite growth cycle of aquatic to terrestrial life) race to find cover where ever possible in order to avoid being eaten by pterosaurs or even older nymphs. The nymphs then live the next four years of their life on the island, living on small prey and scavenging whatever the ocean spits up as they grow. These animals grow in a strange way however, while the rest of their body grows, sometimes up to 2.5 ft a year, the legs grow very slowly, and at about four years the nymphs are forced to crawl on the ground. At the end of four years the babies are 10 ft long, and the surviving nymphs, all crawling by this point, instinctively make their way to the ocean, where they will live most of the rest of their lives.
*gasp* Its Tyrannomedon! He's back!
Yes, this creature should've existed.